At some point in the growth of Facebook, Mark realized that what he had said back then was wrong and he is accountable for all the information people were giving Facebook. If he had continued with his attitude of people being "dumb" for giving him all the data after that point, I don't think Facebook would have succeeded as it has up until today.

So I guess you don't always have to 'fail' to learn a life lesson, but as you gain different perspectives on things you also learn from that.

I think a perfect example is politics. When you know only a little information about a topic, it's easy to say, 'just do this', or 'why are the idiots in office not doing it this way.' However, once you get more involved, and you see the repercussions of every decision you make, etc., you have a very different view.