I think now of this opening of Enter Laughing by Joan Rivers. She was quite the stand up in her day:

"You want to hear stupid? Major stupid? Stand up comic. You walk onto a bare stage absolutely alone, no comfort, no help, no script or actors to support you, no lyrics and music to give you life - just yourself saying your own words out of your own head, telling each person one on one, the weirdest corners of your psyche. And everybody is judging your personality, judging whether you are worthy of their money, whether you make them happy. When they do not laugh, that silence is a rejection of you personally, only you. Not your mother. Not your piano player - if you have one. A thousand people in a room are saying, "You stink. You're nothing."

But here's what is even more stupid. In order to get on that stage and walk that terrible tightrope, you struggle through years of humiliation and privation, feeling like the misfit of the world. For this job you have to be nuts, but it is the craziness that makes you funny, makes you obsessed with your career. It is craziness that makes you live for that hour facing an audience which can destroy you at any moment. Yet, those are the truly happy times in my life, riding the laughter higher and higher, feeling that euphoria, feeling washed in love."