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.
Every generation imagines itself to be more intelligent than the one that went before it, and wiser than the one that comes after it.
Take everything you like seriously, except yourselves.
Leadership is about empowering others to achieve their best, not just giving orders.
I think goals should never be easy, they should force you to work, even if they are uncomfortable at the time.