Peter Thiel on the most important lesson he learned in venture capital

Once something works, people often underestimate it. And when things aren't working, they underestimate how much trouble they're in. The biggest mess of the last decade was not doing our pro rata or for that matter, the full series B at Facebook. It was a 12x up round in eight months. It was the steepest up round in that amount of time in any company we've been involved in. And in retrospect, that was perhaps also the cheapest. And I think one of the reasons it was so underpriced was investors don't want to step up that much. But then even the people on the inside often underestimate how much things change. Even though you had these abstract charts that were, you know, going exponential on the inside, it didn't feel things were changing that much. And that's why people underestimated. And so you have these subtle but very important points where somehow the leverage shifts, where somehow the dynamics shift very powerfully and they tend to get very underestimated.