In 2008 SpaceX had launched three rockets. They all failed to achieve their goal of getting into orbit. A little after the third attempt Elon Musk was interviewed by wired magazine.
This excerpt made me smile.
Wired: At the end of the day you're still zero for three; you have so far failed to put a rocket into orbit.
Musk: We haven't gotten into orbit, true, but we've made considerable progress. If it's an all-or-nothing proposition then we've failed. But it's not all or nothing. We must get to orbit eventually, and we will. It might take us one, two or three more tries, but we will. We will make it work.
Wired: How do you maintain your optimism?
Musk: Do I sound optimistic?
Wired: Yeah, you always do.
Musk: Optimism, pessimism, fuck that; we're going to make it happen. As God is my bloody witness, I'm hell-bent on making it work.