"Most people don’t know what they want or feel. And for everyone, myself included, it’s very difficult to say what you mean when what you mean is painful. The most difficult thing in the world is to reveal yourself, to express what you have to. As an artist, I feel that we must try many things – but above all, we must dare to fail. You must have the courage to be bad – to be willing to risk everything to really express it all." - John Cassavetes
That's about as true a statement for an artist, regardless of the medium, as you can get. Of course, I think it's also true about all professions, and life in general, but it's in the arts that the principle is put into practice in the most public of ways.