Elon Musk on how he makes predictions: I generally try to get the estimate to the nearest order of magnitude.

Herbert Ong: “We want to understand how you think. For example, in the Master Plan Part II, you calculated it takes 6 billion of FSD miles driven before maybe the regulators would approve it. How did you know?”

Elon: “I generally try to get things to within an order of magnitude. So, it seemed to me like probably, and this was technically in kilometers, but it would be closer to 10 billion kilometers, which is roughly 6 billion miles than it would be to 1 billion. But I thought it would not take 100 billion kilometers. When you're trying to guess something where there's a lot of uncertainty, just try to get the estimate to the nearest order of magnitude, the closest factor of 10. And that's why I said, you know, probably around 10 billion kilometers or 6 billion miles.”

Tesla Shareholder Meeting, November 6, 2025