I find it funny that capitalism requires what is essentially an irrational behavior. It seems to me that big public corporations, which avoid risk, and only buy startups once they have been established, are the rational actors. On the other hands, three guys in the garage doing a startup often do it not because they calculate expected profits, but because they want to do it for other than monetary reasons - typically…
Similar in some ways to how evolution depends mutation?
So even if those guys in the garage act irrationally as individuals, someone has to take those risks, otherwise the society as a whole would be out-competed.
And that's why some people have evolved (not me :-)) to take more risks, at the personal expense.