It comes down to two things. One is the well documented issue of how, when you are that rich, you are treated differently, and how that will ultimately modify your behavior. The other is the prerequisites to get to the job. Chances are you aren't fully self-made, receiving no investment. From convincing investors, to having immense faith in a project that cannot be obviously good, as otherwise you'd be building what already exists, to the personality to handle the road upward.

This second effect happens in all kinds of places where you have to jumps througha lot of hoops to just get to get there. Every hoop discards candidates, and promotes different things. Sometimes in ways that make sure that nobody capable of attaining the job is fit to actually do it well. You can see the issue all over the place, once you track people's careers. Sometimes things that should be disqualifying for a role are actually requirements in practice.