“We underestimated the scale… I underestimated the scale that a single client operates at nowadays. Five years ago, if you're talking about a 30-megawatt data center, it was a serious facility. By now, 30 megawatts sometimes is not enough for a single client, which I'm still getting used to.”
Unsupervised Learning with Jacob Effron · AI Builders · November 2026
Context
Asked about his biggest mistake building Nebius, he says he misjudged how large individual AI customers have become, in both power and storage throughput.
Transcript
…agents will not touch the core services for a while because this is out of bounds. Sometimes people are surprised that I work in a company that kind of participates in this whole AI revolution and I'm very conservative. But at the same time, I've seen how this source is made. And I'll be cautious.
What's the biggest mistake you feel like you've made in building Nevius so far? Obviously, a lot's gone right, but I'm curious, something that in retrospect you wish you guys had done differently.
It might sound funny these days, but we underestimated the scale. And it's not about the growth of the company. We were pretty optimistic from the very beginning. But I personally, that was my strong bias for the first significant part. I underestimated the scale that a single client operates at nowadays. Five years ago, if you're talking about a 30-megawatt data center, it was a serious facility. It hosted hundreds of thousands of servers, like run…
Yeah.
Still puzzling.
It's crazy. And I guess lastly, there's obviously a lot of unsettled questions in the AI field today that lots of people are trying to figure out where the world goes. I'm curious, like, you know, what you're paying attention to. And I guess, you know, with a lens toward, you know, if it goes one…
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