Steven Sinofsky

Things Steven Says on Podcasts

Ran Microsoft's Windows division for years before leaving the company in 2012, and now serves as a board partner at the venture firm Andreessen Horowitz (a16z). Writes the newsletter Hardcore Software about his time at Microsoft and is a frequent guest and host on the a16z Podcast, where he argues that AI failures get treated as mysterious safety problems instead of debugged as ordinary engineering bugs.

Where to Find Them

Steven Sinofsky writes Hardcore Software by Steven Sinofsky , hosts and writes a16z Podcast , writes a16z and writes AI + a16z . They have also been a guest on Console DevTools and TBPN .

Recently: “243. Government(s) Controlling AI Sounds Safer, But…” on Hardcore Software by Steven Sinofsky (September 2026); “Aaron Levie, Steven Sinofsky & Martin Casado: How Do You Secure a World of AI Agents?” on a16z Podcast (September 2026); “Aaron Levie, Steven Sinofsky & Martin Casado: How Do You Secure a World of AI Agents?” on a16z Podcast (September 2026); “AI Safety Language Is Destroying the Debate | Steven Sinofsky” on a16z Podcast (September 2026); “AI Safety Language Is Destroying the Debate | Steven Sinofsky” on a16z Podcast (September 2026); “242. Armageddon by Anthropomorphism: On Security and the Frontier” on Hardcore Software by Steven Sinofsky (August 2026).

What They Said

“There's been no user study ever that shows interacting with the computer using full natural language is efficient. It's literally always the least efficient way. Ask yourself: how many people are really good at asking questions? Immediately, that's less than half the people who can ask a good question in a meeting.” — Steven Sinofsky, a16z Podcast

Sinofsky, who ran Windows at Microsoft, is enthusing about Vercel's Jev — a model that reads text but returns a choice from a set of options rather than generating prose, which makes it cheap to embed in ordinary software. His point is that chat was always the wrong default interface, and that what's coming back is probabilistic programming, which he notes was most of computer science before 1970.

a16z Podcast · 2026-09-26 Permalink → Listen →
a16z Podcast Around 52:13 into the episode
Erik Torenberg

remarkable. Yeah.

Martin Casado

Well, okay. So the way I think about it is, so, okay, so LLMs were kind of text in text out, right? They generate text. And they came from chat, right? It was to communicate with a human. And we've spent the last few years trying to take this thing that spits out text and cram it into a traditional program, right? And but traditional programs don't really speak text, right? And so then you end up doing this janky thing where you're like in the prompt, you're like, here's this demon, here's the schema. But the thing is generating text and it kind of ignores it. And it's just been super janky. And so what Jeff basically said is that, listen, you know, generating the text on the outside is a very expensive thing, but it's also kind of, you know, it's more complicated than you need. So why don't we, we, will, we'll, we'll read text and we'll have all of that kind of knowledge to read the text. But then rather than generating text, which is very expensive, we will just, if you give us a set of options, we'll choose the best option. We can do that incredibly, we can do it incredibly fast, incredibly cheaply, but also we can do it with much more accuracy because we can train just for this. And so for all of the use cases that are not talking to like a chat bot, but are actually trying to put it in traditional software, this is a great fit. And so this has probably been the fastest adoption of an AI model since ChatGPT. It's just been remarkable because we're all primed for this. I

Steven Sinofsky

just want to pile on this one because I. I can't tell you how much I love seeing this exact form of innovation. And because what it does is it does the thing that's bugged me from the very beginning, which is there's been no user study ever that shows like interacting with the computer using full natural language is efficient. It's like literally always the least efficient way. And it's very simple. And it's just like, ask yourself, how many people are asked, are really, really good at asking questions? And immediately that's like less than half the people can ask a good question in a meeting. And then how often do you look at the answer and get really frustrated before it's finished, but you have to pay all this money to watch the seven paragraphs come out and then apologize that it's only a little. And so that's one, like having a different model. And then the other, of course, is my favorite, which is the output of it is designed for probabilistic programming. And so instead of saying, like, is this a customer service question, then route to customer service, otherwise route to general help desk or whatever, it's like, well, this is 80% customer service. And that's exactly simulation. And it turns out there's like 50 years of computer science research in literally like probabilistic if statements. And so suddenly the coolest place to be in computer science is going to be in probabilistic programming, which was like all of computer science in the 1960s and 70s. So it was basically how do we, because all of computers started with doing math and it was all simulation. So it was like, let's launch the missile and hit that target, but it's windy, but wind isn't constant. So like, let's model the wind and decide where to put the thrusters in order to do the art. And so most programming through like, say, 1970, before it got to accounting, was probabilistic. And then we ruined everything. No, in accounting, there's no probability in accounting. But most programming was basically this modeling kind of thing. And so most programming language design was trying to figure out how to put probability into if statements or into while loops, like do this until something happens, maybe most of the time. And like, so my first CS class, like the very second assignment or so was a simulation about like waiting online at a store. And I didn't know it at the time. I actually looked all this up when I was reading about Jeb, which was like the whole thing was my professor was like wrote the book called the Theory of Simulation in like 1960. And I just didn't know that because it was kind of died by the 80s because it was all replaced by hyper. And so this notion of probabilistic and that slide deck you shared about the future of what's different about language models and stuff that you said was super good. Oh,

Martin Casado

Halper Flanks one. That was phenomenal, Thomas. But the

Steven Sinofsky

part that

Aaron Levie

I felt was missing was that like, oh, wait, this is not all new. Like all of computer science was this probabilistic stuff. And so it's going to be very interesting to dust off all of that work because it's exactly what's going on. Like it's not an if statement now is if X percent, not if always. And so the way that Jev worked is just to like, you, you basically, it's a custom programming language almost, which is here's the prompt, come back with a percentage. Yeah,

Speaker names from our own diarization · position estimated from where the line sits in the episode
“The AI people are making it impossible for anybody to understand what they've done. They're using words like 'the AI failed to be aligned.' What does that mean? It means there was a bug in the software. When Word ate your file and deleted all your content, we didn't think demons had taken over Word and made it do things against the will of man.” — Steven Sinofsky, a16z Podcast

Sinofsky ran Microsoft's Windows division for years and is now a board partner at a16z. He was asked about the Stop Rogue AI Act and the wave of AI bills that followed the OpenAI agent incident, and his argument is that the vocabulary of AI safety — alignment, goal-seeking, rogue agents — is doing the damage, because it turns ordinary engineering failures into something mystical that only outside authorities can fix. His prescription is the unglamorous one: better telemetry, debugging and incident reporting.

a16z Podcast · 2026-09-21 Permalink → Listen →
a16z Podcast Around 00:00 into the episode
Steven Sinofsky

The AI people are making it impossible for anybody to understand what they've done. And they're using words like, well, the AI failed to be aligned. Okay, what does that mean? What it means is there was a bug in the software. When Word ate your file and deleted all your content, we didn't think that demons had taken over Word and made it do things against the will of man. But software doesn't do what it's supposed to do. It's a bug.

Speaker 2

When AI does something we didn't expect, is it misaligned or does the software just have a bug? A16Z board partner and former Microsoft Windows president Steven Sinofsky joins Theo Jaffee and Sofia Puccini on MTS to argue that the language around AI safety is making the technology harder to understand. Drawing on decades of building software, Stephen explains why AI labs need better telemetry, debugging, and incident reporting, and what today's industry can learn from earlier software failures, computer viruses, and Y2K. They also discuss why terms like alignment, goal seeking, and rogue agents can distort the policy debate and why treating AI more like software could lead to clearer conversations about both safety and regulation.

Steven Sinofsky

We are live with Steven Sinofsky, who is a board partner at Andreessen Horowitz. He's a seed investor, author of the Substack and the book Hardcore Software. Previously, he was the president of Microsoft's Windows division, engineering and marketing across Windows, Windows Live, and Internet Explorer. And he posts on Twitter at Steven Sinofsky. Steven, welcome back. Howdy. So we were just talking about, we're in DC right now at the FAI office. Out of FAI. Yeah, we're at FAI. And we've been talking about all of the new regulation and new laws that have been proposed for the AI industry over the last few weeks, including the Stop Rogue AI Act, which was proposed by Josh Gottheimer of New Jersey. And you're offering some thoughts on this. What's your take? Well, sure. Well, right now we're in the maximal phase of like, let's just throw tons of legislation out there. So, real quick, I'm just going to take you back. I can't believe we're going to take you this far back. This is going to seem like infinity years ago in another dimension of time and space. But in 1983, I was a freshman in college. And one day in the fall, like, and there were two people in our 100-person dorm that had computers, me and another guy. And that was it. And there was nothing to do with them. Nobody knew why we had them, blah, blah, blah. And one day, literally, G-Men in suits crashed our dorm, confiscated the other guy's computer, and arrested him. Wow. And it turns out, fast forward a little bit, blah, blah, blah. He was part of a hacker group, one of the very, very, very first hacker groups called the Inner Circle or the Inner Ring. And they were hacking this thing called GTE Telemail. GTE was a big communications company, and it was one of the very first online mail services that you used a modem and you dialed up and you could just mail other people in telemail. Who were some of the clients of it? The United States government and NASA in particular. And immediately after this series of arrests, they arrested people all over the country in this coordinated sting operation. I mean, imagine I'm a freshman in college and they just carted this guy off with his IBM PC XT that weighed 50 pounds at a giant monitor. And it was like a freshman in the same, we were the computer science majors together. And it turns out that there was no crime committed. It wasn't illegal to do what they were doing. There was no law that they were violating.

Theo Jaffee

Oh, wow.

Speaker names from our own diarization · position estimated from where the line sits in the episode

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