I came through this amazing story on Quora:
In the very early days of Facebook, when it had fewer than 15 employees, a guy nameddecided after working there for only a few weeks that it just wasn’t for him. He wanted to leave to found his own company, and his plan was to do a video startup.
, the guy who had hired him in the first place, tried to convince him otherwise. “You’re making a terrible mistake. Facebook is going to be huge! And there’s already a ton of video sites. If you do this you’re going to regret it for the rest of your life!”
Chen wasn’t convinced, so he decided to do it anyway and left to start a company called YouTube.