I knew that if I failed I wouldn't regret that, but I knew the one thing I might regret is not trying.
If you do build a great experience, customers tell each other about that. Word of mouth is very powerful.
If you're not stubborn, you'll give up on experiments too soon. And if you're not flexible, you'll pound your head against the wall and you won't see a different solution to a problem you're trying to solve.