If there's ever an example of the importance of making bold bets and focusing on what you love, it's Twitter.

Not only can you not plan the impact you're going to have, you often won't recognize it even while you're having it.

People have Plato's form in their mind of what a leader is, or what a C.E.O. is, and it is a bunch of elements that I really don't conform to at all. I've given this a lot of thought, and I came to the conclusion that I don't care.

Twitter brings you closer. I mean, we see this over and over again from our users. It brings them closer to the action. It brings them closer to their heroes.