Why AI Products Fail: Non-Determinism, Agency vs. Control, and Continuous Calibration

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Overview

Aishwarya Naresh Reganti ("Ash") and Kiriti Badam have worked on or supported more than 50 AI product deployments at companies including Amazon, Databricks, OpenAI and Google, as well as startups and large enterprises. Kiriti works on Codex at OpenAI and previously spent about a decade building AI and ML infrastructure at Google and Kumo. Ash was an early AI researcher at Alexa and Microsoft, has published more than 35 research papers, and now runs a consulting practice and startup. Together they teach a course on building AI products.

32 min read

In this conversation with Lenny, their argument is that AI products fail when teams build them like traditional software. They say two properties change the development lifecycle: non-determinism, and a trade-off between the agency given to an AI system and the control the humans keep. From those two ideas they derive a practice they call "continuous calibration, continuous development": start with narrow autonomy, log what humans do, watch for behavior you didn't expect, and expand what the system is allowed to do only after it has earned trust.

6:00

What changed between 2024 and 2025

Ash began with what she sees from the ground in her consulting work. In her view, 2025 differed from 2024 mainly because skepticism dropped. In 2024, many leaders suspected AI might be "yet another crypto wave." Many of the use cases she saw were essentially chat over a company's own data, marketed as an AI product. In 2025, she sees many more companies rethinking user experiences and workflows. They accept that building a successful AI product requires deconstructing and reconstructing existing processes.

The bad news, as she sees it, is that execution is "still all over the place." She notes the field is about three years old and has no playbooks or textbooks. The AI lifecycle before and after deployment differs from the traditional software lifecycle. As a result, old contracts and handoffs between PMs, engineers and data people have broken down. Previously each role optimized its own feedback loop. Now, she says, these people probably need to sit in the same room, look at agent traces together, and decide how the product should behave. Companies are still learning to work in that tighter way.

8:07

The first difference: non-determinism on both input and output

Ash stressed that AI systems and conventional software share many similarities. But she named two differences that she says fundamentally change how products are built. The first, which she thinks most people ignore, is non-determinism.

She used Booking.com as the contrast. In traditional software, a user who wants two nights in San Francisco has an intention. The product is a well-mapped decision engine that converts that intention into an action through buttons, options and forms. In AI products, that layer is replaced by a fluid, mostly natural-language interface. Users can express the same intention in countless ways, so the builder no longer knows how users will behave. On the output side, the builder works with an LLM, which she describes as a non-deterministic, probabilistic API that is sensitive to prompt phrasing and essentially a black box. So builders are dealing with an input, a process and an output, none of which they understand well. They are trying to anticipate behavior and build for it. With agentic systems, she says, this gets even harder.

She also offered the upside of the same property. People are more comfortable talking than clicking through buttons, so AI products lower the bar to use. But there are many ways to communicate. Most of the surrounding systems are deterministic, and teams want deterministic outcomes from a non-deterministic technology. "That's where it gets a little messy," she said.

10:08

The second difference: the agency–control trade-off

The second difference is what they call the agency–control trade-off. Ash said she is surprised how few people discuss it, given how obsessed many teams are with building autonomous agents. Every time decision-making capability is handed to an agentic system, she argued, the builder gives up some control. More agency means less control. So the builder must make sure the system has earned that ability, meaning it has become reliable enough and has built up trust over time.

Kiriti framed the practical consequence with an analogy. If the goal is a very long, hard hike, you don't attempt the full route on day one. You train on smaller parts and build up. Similarly, he argued, teams should not start with agents wired to every tool and all of the company's context and expect them to work. Teams should deliberately start where impact is minimal and human control is high. That way they learn what current capabilities are, what problem the AI actually solves and to what extent, and what context and tools to add next. He sees a good side to this. Nobody needs to feel intimidated by impressive-looking agents elsewhere, because everyone starts from minimal structures and evolves them. He says this pattern repeats "over and over" in their work.

13:50

Climbing the ladder: examples of graduated autonomy

Kiriti's main example was customer support, which he said OpenAI itself faced. Launches such as the image model or GPT-5 caused spikes in support volume and brought new kinds of questions. The wrong move, he said, is to dump every help center article into an agent. A staged approach starts with AI suggesting answers to human support agents. The humans signal which suggestions are good or bad in particular cases. That feedback exposes the system's blind spots so they can be fixed. Only then does the system graduate to answering customers directly. After that, new capabilities can be added, such as issuing refunds or filing feature requests with engineering. Starting with all of this on day one, he said, makes the complexity "incredibly hard to control."

Ash described the higher-level idea as "behavior calibration." It is effectively impossible to predict up front how the system will behave, so the goal is to avoid damaging the user experience while gradually reducing the amount of control humans need to exercise. There is no single right way to constrain autonomy. Her example was insurance pre-authorization, which she called a very promising use case because clinicians spend a lot of time pre-authorizing blood tests, MRIs and similar procedures. Blood tests and MRIs are relatively low-hanging fruit, since approval is easier once the patient's information is known. Invasive surgery is higher risk and should not be approved autonomously. Teams can decide which cases go through a human-in-the-loop layer and which the AI can handle. Throughout, they log what the humans do, to build a flywheel that improves the system without eroding trust.

Lenny read two further progressions from their earlier guest post. For a coding assistant, the stages run from inline completions and boilerplate, to larger blocks such as tests or refactors for human review, to applying changes and opening PRs autonomously. For a marketing assistant, they run from drafting emails or social copy, to building and running multi-step campaigns, to launching, A/B testing and auto-optimizing campaigns across channels.

20:10

Why starting small forces a "problem-first" mindset

Lenny suggested that teams get into trouble when they jump straight to the V3 stage. Kiriti agreed. When an agent is doing things wrong "in like 100 different ways," teams can't realistically tabulate and fix all of them, even with good evaluation practices. Starting in the wrong place makes correction very hard.

He pointed to a less obvious benefit of starting with high control and low agency: it forces teams to think about what problem they are actually solving. They use the term "problem first." Kiriti said the idea seemed obvious to him, yet it resonates strongly with people. Amid rapid AI progress, he said, an easy slippery slope is to keep thinking about the complexities of the solution and forget the problem. Starting at a small scale of autonomy makes teams break the problem into levels of autonomy they can build toward later.

Ash cited a recent paper from researchers around Matei Zaharia at UC Berkeley and Databricks. According to her reading, about 74–75% of the enterprises surveyed named reliability as their biggest problem. That was why they weren't comfortable deploying customer-facing products. The authors also connect this to why so many current AI products focus on productivity, a lower-autonomy category, rather than end-to-end agents that replace workflows. She said this matches what her startup sees.

A brief detour on prompt injection

Lenny mentioned an earlier episode on prompt injection and jailbreaking, which that guest had described as possibly an unsolvable problem with guardrails that are easy to get around. Ash predicted it will become a huge problem once systems go mainstream. For now, she said, teams are too busy building to worry about security. Because the underlying API is non-deterministic, there are many instructions that can be injected into a prompt.

Kiriti took a more optimistic line. He agreed it is a real problem. But he argued that adoption is still at a very early stage, even though 2025 was a busy year for agents, and that penetration is far below what companies could benefit from. With the right human-in-the-loop checkpoints, he believes many of these risks can be avoided while companies streamline their processes. He said companies need to try adopting AI rather than focusing only on what could go wrong. Among the companies he has talked to at OpenAI, he said, none has concluded that AI cannot help them at all. There has always been some set of things it could optimize.

25:53

The success triangle: leaders, culture, technical practice

Asked what distinguishes companies that build AI products successfully, Ash described a "success triangle" with three sides: leadership, culture and technical progress. "Every technology problem is a people problem first," she said.

On leadership, her point is that leaders have built intuitions over 10 or 15 years and are respected for them. With AI, those intuitions must be relearned, and that requires vulnerability. Her example was Gajen Kandiah, now CEO of Rackspace, with whom she used to work. Gajen blocked out 4 to 6 a.m. every day for "catching up with AI," with no meetings, to take in podcasts and other information. Gajen also held weekend vibe-coding sessions. According to Ash, Gajen relied on a short list of two or three trusted sources. Afterwards Gajen would bring questions to a group of AI experts, which she was part of, and said this learning trickled down into company decisions. Leaders need to be hands-on, she argued, not to implement things but to rebuild intuition. They should accept that their intuitions may be wrong and that they may be "the dumbest person in the room." She believes this has to come top-down. Engineers can't win buy-in from a leader who distrusts the technology or has misaligned expectations. She has heard from many builders that their leaders either underestimate what AI can do, or vibe-code something and assume it will be easy to take to production.

Lenny connected this to an earlier conversation with Dan Shipper, who had said the number one predictor of a company's AI success is the CEO using ChatGPT, Claude or similar tools many times a day.

On culture, Ash said many enterprises where AI isn't the core business adopt it because competitors are doing so. That often creates a culture of FOMO and "you will be replaced." This is harmful because subject matter experts are essential. Teams need them to understand how the AI behaves and how it should behave. Yet she has spoken with companies whose experts won't engage because they believe their jobs are being replaced. Leaders should instead build a culture of empowerment, where people add AI to their own workflows to "10x" what they do, rather than guarding their jobs. She added that AI opens up more opportunities than before.

On the technical side, she says successful teams are obsessed with understanding their workflows. They decide which parts suit AI and which need a human in the loop. Automating part of a workflow is rarely just a matter of "use an agent." Usually some part is done by a machine learning model and some by deterministic code, and teams need to pick the right tool for each part rather than fixate on the technology. These teams also understand that working with a non-deterministic API changes the lifecycle. They iterate quickly in ways that don't damage the customer experience but still produce enough data to estimate behavior. "It's not about being the first company to have an agent among your competitors," she said. "It's about have you built the right flywheels in place so that you can improve over time."

30:54

Skepticism about "one-click agents"

From that followed a strong claim. If someone promises a one-click agent that will show significant gains within two or three days, Ash would be skeptical. The reason, she said, is not model capability but messy enterprise data and infrastructure. Taxonomies are messy. Tech debt accumulates, with functions like "get customer data v1" and "get customer data v2" both existing and both being called. An agent needs time to understand these systems. She called one-click agent pitches "pure marketing." She would prefer a vendor that builds a pipeline which learns over time. In her estimate, replacing a critical workflow or getting significant ROI "easily takes four to six months of work," even with the best data and infrastructure layer.

33:35

Evals versus production monitoring: a false dichotomy

On the evals debate, Kiriti called it a false dichotomy to believe that either evals or production monitoring alone will solve everything. He described evals as a team's product knowledge encoded into datasets: what matters, and what the agent must never do. Production monitoring means deploying and tracking key metrics that show how customers actually use the product. He noted that production monitoring has existed for a long time. With AI agents it needs finer granularity and must include implicit signals. His example was ChatGPT: users may not give a thumbs-down, but if they regenerate an answer, that is a clear sign the first answer missed expectations.

He described how the two fit together. Nobody ships without some testing, whether vibes or a set of ten questions that must never go wrong. Call that an evaluation dataset. After deployment, a high-traffic product can't have every trace reviewed by hand. Explicit and implicit signals tell the team which traces to look at. Examining those traces reveals failure patterns. If a pattern is something the team truly cares about, it becomes a new evaluation dataset. His example was an agent offering refunds even though it had been explicitly configured not to. After fixing tools or prompts and shipping a second version, there is still no guarantee that this was the only problem, so monitoring remains necessary. The view that only one approach is needed is, in his words, "completely dismissible."

Ash added that "evals" had to carry an enormous amount of meaning in the second half of 2025. Data labeling companies say their experts write evals. Commentators say PMs should write evals, calling them "the new PRDs." Others say evals are the whole feedback loop. She argued these refer to different parts of the process. When lawyers or doctors at a labeling company "write evals," they are doing something closer to error analysis or annotation, not building LLM judges. When people say a PM should write evals, that doesn't mean a production-grade LLM judge. She invoked Martin Fowler's term "semantic diffusion": a term gets redefined by everyone until it loses its original meaning. She believes practitioners would all agree on the underlying need, an actionable feedback loop for AI products. How to build it depends on the application. In complex use cases, she said, LLM judges become very hard to build. New patterns keep emerging that a judge, for example one testing for verbosity, doesn't catch. Teams can end up with too many evals. At that point it may make more sense to look at user signals, fix issues, check for regressions and move on. Her advice was to avoid being obsessed with prescriptions, because they will change.

She also told of a client who said they "do evals." When she asked for their dataset, they explained that they checked LMArena and Artificial Analysis to choose a model. Those are model benchmarks, she told them, not evals.

41:29

How the Codex team approaches evals

Lenny raised the head of Claude Code's remark that the team doesn't do evals and relies on vibes, and asked how Codex handles it. Kiriti described a balanced approach. He said coding agents differ from agents in other domains because they are built for engineers and for customizability. They are not meant to solve five or six fixed workflows. They are used across many integrations and tools, which makes it very hard to build eval datasets covering every interaction. Still, the team keeps evaluations to make sure changes don't damage core functionality.

At the same time, Kiriti said, the team pays close attention to how customers use the product. His example was a recently launched code review product, which he said has gained a lot of traction and has caught many bugs both inside OpenAI and for external customers. If the team changes the model behind code review or trains it with a different RL mechanism, they want to A/B test whether it finds the right mistakes and how users react. Users annoyed by incorrect reviews sometimes switch the product off entirely, and that is a signal worth watching. He said such scenarios are very hard to anticipate in advance. The team also watches social media closely for reported problems. When a new model arrives, team members each focus on different areas and run a shared list of hard problems against it, which he described as something like custom evals for each engineer. He doesn't believe anyone who claims to have a concrete set of evals they could bet their life on without needing anything else.

45:55

The CC/CD framework: continuous calibration, continuous development

The centerpiece of their work is the framework they call continuous calibration, continuous development (CC/CD), named as a nod to CI/CD. Ash explained the backstory. Many companies feel competitive pressure to build fully autonomous agents, and she worked with a few customers on end-to-end agents. Because nobody knew in advance how users would interact or how the AI would respond, debugging a workflow of four or five steps with many decisions became overwhelming. In one customer support project, the example used in their guest post, the team had to shut down the product because of how many hotfixes they were making. There was no way to keep up with the problems that kept emerging. She also cited the Air Canada case, where, as she put it, an agent hallucinated a refund policy that wasn't in the company's playbook, and the airline had to honor it for legal reasons. The framework aims to preserve customer trust, avoid dangerous decisions, and still build a flywheel for improvement.

The development side of the loop starts with scoping capability and curating data: a set of expected inputs and expected outputs. Ash considers this worthwhile before building any AI product, because it often reveals that the team isn't aligned on how the product should behave. This is where PMs and subject matter experts contribute a lot. The dataset isn't comprehensive, but it's a starting point. The team then sets up the application and designs evaluation metrics. She deliberately uses "evaluation metrics" rather than "evals": evaluation is the process, and metrics are the dimensions measured during it. Then the team deploys and runs those metrics.

The calibration side deals with behavior nobody expected. Users almost always behave in ways the original dataset didn't anticipate. Metrics offer some insight, but new error patterns often appear that the metrics don't cover. The team analyzes behavior, spots error patterns, applies fixes, and designs new metrics for emerging patterns. Not every error needs a new metric, though. A one-off tool-calling failure caused by a poorly defined tool can simply be fixed.

Across these iterations, the framework calls for low-agency, high-control versions first, with autonomy increased over time. Ash walked through the customer support example in three versions.

Version 1: routing. The agent classifies tickets and routes them to the right department. It may sound trivial, but Ash said routing in enterprises can be very complex because of messy hierarchical taxonomies. In one case she worked on, "shoes," "women's shoes" and "men's shoes" all sat at the same level. Further down, another section under shoes said "for women" and "for men" and was never merged. A human agent might notice that a node was last updated in 2019 and treat it as dead. She said she isn't claiming models can't handle this. Her point is that enterprises have undocumented rules, and agents need that context rather than simply being handed the problem. Routing is a high-control stage, since humans can correct misroutes. It also surfaces data issues that must be fixed so the data layer is good enough.

Version 2: copilot. Once routing works and data issues are fixed, the agent drafts responses based on the support team's standard operating procedures, and human agents edit them. The system logs how much of each draft was used and what was omitted. Ash called this getting "error analysis for free," which feeds back into the flywheel.

Version 3: end-to-end resolution. When drafts are mostly used as-is with few edits, the agent drafts a resolution and can also close the ticket.

Their table for each version lists what is done, what is learned and what feeds back into the loop. Routing, for example, produces better-quality routing data and shows how prompts should be structured, which she calls figuring out the structure for context engineering.

Ash added two caveats. First, CC/CD doesn't solve problems once and for all. A team may reach V3 and still meet a data distribution nobody imagined. It is one way to lower risk by learning how users behave before reaching full autonomy. Second, to people who ask why this is needed when evals exist, she answered that evaluation metrics catch only the errors a team already knows about. Emerging patterns show up only in production, and the framework provides a lower-risk way to find them without facing a flood of errors at once. Autonomy can be constrained in other ways too. The example constrains the number of actions, but teams could constrain by topic, since some domains are too risky for full autonomy while others are fine. PMs, engineers and subject matter experts should decide this together.

58:24

Knowing when to move to the next stage

A common question is how to tell when a stage is calibrated enough. Ash said there is no rule book, but the principle is "minimizing surprise." If a team calibrates every day or two and stops seeing new data distribution patterns, and user behavior is consistent, the information gained is low and it is probably time to move on. She acknowledged that at that point "it's all about the vibes."

Events can also throw calibration off. Her example was GPT-4o being retired, including in the API. Companies must switch to GPT-5, which she said has very different properties, so they need to recalibrate. User behavior also changes over time. People talk to ChatGPT differently now than two years ago as capabilities have grown, and people who see a system solve one task want to try it on others.

Her clearest example was a system built for a bank's underwriters. Loan applications can run 30 or 40 pages, and the system helped underwriters find relevant policies and bank information to approve loans. For three or four months everyone was impressed, and underwriters reported time savings. Then, she said, they became so enthusiastic that they began asking questions nobody had anticipated. They would drop in an entire application and ask what previous underwriters did "for a case that looks like this." To users this felt like a natural extension. For the builders it required very different engineering. The system had to interpret what "a case like this" means, whether a certain income range or a geography, then retrieve and analyze historical documents rather than simply look up a policy. Something that seems natural to an end user can be very hard to build, she concluded, and when behavior evolves like this, it's time to recalibrate.

1:01:36

Overhyped and underhyped

Kiriti said he wouldn't call anything overhyped, but he thinks multi-agent systems are misunderstood. The common idea is to split a complex problem into agents by function, connect them, and expect "agent utopia." He agreed there are successful multi-agent systems, and named the supervisor agent with sub-agents as a successful pattern. What he doubts is dividing responsibilities by function and expecting agents to coordinate peer-to-peer through something like a "gossip protocol." He doesn't believe current building practices and model capabilities are there yet. Humans can orchestrate multiple agents, or one larger agent can orchestrate. In peer-to-peer setups, especially in customer support, it becomes very hard to control which agent is responding to the customer, and guardrails have to be placed everywhere.

As underhyped, he picked coding agents. That may sound odd given the online chatter, but he said engineers at ordinary companies, especially outside the Bay Area, have adopted them far less than their potential impact would suggest. He expects 2025 and 2026 to create a lot of value by optimizing these processes.

Ash joked that she would name evals as overrated, then clarified that she means they are misunderstood, not unimportant. Her real pick for overrated was constantly jumping between tools and chasing the newest one. "Building is really cheap today," she said, while design is more expensive. Deeply understanding the problem and the design is underrated, and building for its own sake is overrated.

1:05:30

What 2026 might look like

Kiriti expects progress in background or proactive agents. In his view, AI mostly fails to create value today because it lacks context, since it isn't plugged into where work actually happens. As agents gain context, they can understand what metrics a person optimizes for and what they're trying to do, and then prompt the user back. He cited ChatGPT Pulse, which gives a daily update of things a user may care about. He imagines a coding agent that tells you at the start of the day that it has fixed five of your Linear tickets and the patches are ready for review. He sees this as a strong direction for products in 2026.

Ash is betting on multimodal experiences. She argued that humans are multimodal and language is "probably one of our last forms of evolution." In conversation people constantly adjust based on signals like nodding or boredom, which she described as "a chain of thought behind your chain of thought." Richer multimodal systems could come closer to human conversational richness. She also pointed to mundane work: many handwritten documents and messy PDFs can't be parsed even by the best models today, and better multimodal understanding would unlock a lot of data.

1:08:41

Skills that matter: judgment, agency, persistence

Asked which skills builders should develop, Ash said implementation will become "ridiculously cheap" in the coming years, so builders should focus on design, judgment and taste. Early career years have traditionally focused on execution mechanics. AI can now help people ramp up quickly, and after that, she believes, everyone's job comes down to taste, judgment and what is uniquely theirs. That doesn't require seniority. Her example was a recent hire who showed up to a meeting with a self-built, vibe-coded app to replace an expensive task tracker the team had paid for over years, and onboarded everyone to it. She acknowledged that vibe-coded apps have high maintenance costs and may need replacing as the company grows. But she was struck by the agency and ownership involved. People used to a certain way of working attach a cost to building, and younger people attach a much lower one. She suggested this same eagerness to try new tools also explains why AI products have retention problems. She also predicted "the end of the busy work era": people can no longer sit in a corner doing work that doesn't move the needle. Lenny added an anecdote from Jason Lemkin, who replaced most of a sales team with agents. One salesperson quit after an agent began automatically updating Salesforce from calls, apparently because it would have exposed that the salesperson wasn't doing much.

Kiriti emphasized persistence. With information at everyone's fingertips, anyone can learn quickly, but the real advantage comes from going through the pain of learning, implementing and discovering what works. "Pain is the new moat," he said. Asked to expand, he argued that successful companies in new areas succeed not because they were first to market or had a flashy feature. They went through the pain of identifying their non-negotiables and matching them against the features and model capabilities that could address them. There is no textbook or well-trodden path for this. The knowledge built through repeated trial and error, whether in the form of evals or something else, becomes the company's moat.

Ash's closing advice was to be obsessed with customers and the problem, and to treat AI as a tool. She estimated that 80% of so-called AI engineers and AI PMs spend their time understanding workflows, customer behavior and data, not building the fanciest models. Software engineers new to AI are often surprised by the advice "look at your data," she said, but it has always been true, and she sees it as a major differentiator.

1:15:18

Lightning round

Ash recommended When Breath Becomes Air by Paul Kalanithi, a neurosurgeon's memoir written after a lung cancer diagnosis in their early thirties. She highlighted Kalanithi's reply to Socrates' "the unexamined life is not worth living": "was the unlived life worth examining?" She took it as a reminder for people constantly reinventing themselves in the AI era to pause and live. Kiriti recommended the Three-Body Problem series, especially for its theme of how much abstract science matters to human progress and how devastating it is when that progress is halted, even if the effect isn't noticeable day to day. Lenny recommended A Fire Upon the Deep by Vernor Vinge.

For shows and games, Ash is rewatching Silicon Valley, which she finds eerily similar to the current AI wave. Kiriti is playing Expedition 33. Ash's favorite recent product is Wispr Flow. She values that it transcribes with context, recognizing variables in Codex and turning a spoken instruction like adding three exclamation marks into the actual punctuation. Kiriti named Raycast and the caffeinate command, which keeps a Mac awake so a Codex task can run locally for four or five hours.

Ash's life motto came from her father: "they told it couldn't be done, but the fool didn't know it, so he did it anyway." There will always be data suggesting you'll fail, she said, so sometimes be foolish and go ahead. Kiriti, a self-described overthinker, cited Steve Jobs' line that you can only connect the dots looking backwards, as encouragement to keep moving and experimenting. Asked what they admire in each other, Ash praised Kiriti's calm, grounded nature and ability to anticipate problems, then revealed that the two have been married for four years. Kiriti praised Ash's ability to teach and simplify complex topics, combined with persistence, which he says empowers people in a fast-moving field.