A story about meeting choreographer Martha Graham for a soda, as told by Agnes de Mille in Martha: The Life and Work of Martha Graham:
I confessed that I had a burning desire to be excellent, but no faith that I could be.
Martha said to me, very quietly: “There is a vitality, a life force, an energy, a quickening that is translated through you into action, and because there is only one of you in all of time, this expression is unique. And if you block it, it will never exist through any other medium and it will be lost. The world will not have it. It is not your business to determine how good it is nor how valuable nor how it compares with other expressions. It is your business to keep it yours clearly and directly, to keep the channel open. You do not even have to believe in yourself or your work. You have to keep yourself open and aware to the urges that motivate you. Keep the channel open. As for you, Agnes, you have so far used about one-third of your talent.”
“But,” I said, “when I see my work I take for granted what other people value in it. I see only its ineptitude, inorganic flaws, and crudities. I am not pleased or satisfied.”
“No artist is pleased.”
“But then there is no satisfaction?”
“No satisfaction whatever at any time,” she cried out passionately. “There is only a queer divine dissatisfaction, a blessed unrest that keeps us marching and makes us more alive than the others.”
Creative maladjustment. Perpetually blessed and dissed, etc.
(Emphasis mine. Found via The Book Haven, copied from Brain Pickings.)