for instance if that social network film by david fincher hadnt come out, would we have even heard of this mark guy?

Once you go deep enough into a personal passion project like that, you run a serious risk of flunking out of school. For most people that feels like a big deal. And for those of us with fewer alternatives in life, it's usually enough to keep us on the straight and narrow path.

People from wealthy backgrounds often have less fear of failure, which is a big reason why success disproportionately favors that clique. But frankly, most people in that position are more likely to abuse it or ignore it than to take advantage of it. For people like Zuckerberg and Dell and Gates, the easiest thing to do would have been to slack off, chill out, play their expected role and coast through life... just like most of their peers did.