I don't think you understand what being a billionaire is. Zuckerburg has hundreds of millions of dollars in real estate holdings in Hawaii alone. His seat at th

I don't think you understand what being a billionaire is. Zuckerburg has hundreds of millions of dollars in real estate holdings in Hawaii alone. His seat at the top of this list is contingent on Facebook continuing to make him money, but he is wealthy independently of it at this point I get that humans are, by design, way too risk averse, but what do you define "could easily go under" as meaning? What odds would you actually give of these outcomes: Facebook keeps stays a top 10 business for the next 20 years, Facebook stays a top 10 business for the next 5 years, Facebook implodes and is worthless in the next 5 years. I get your point, which I think is extremely narrow, is that "a diverse portfolio is better than a single stack investment plan", but to say you'd prefer to be one billionaire vs being another different billionaire because the first billionaire meets some weird criteria you've devised for determining how best to become a billionaire is not an objective point to be made. TL-dr; you're not playing the same game either of these guys are, and your suggestion that trying to model your life after one vs the other is a weak point to make because of it.