The key is to set realistic customer expectations, and then not to just meet them, but to exceed them—preferably in unexpected and helpful ways.
"The only true voyage of discovery, the only fountain of Eternal Youth, would be not to visit strange lands but to possess other eyes, to behold the universe through the eyes of another, of a hundred others, to behold the hundred universes that each of them beholds."
You have to be willing to make mistakes regularly; there is nothing wrong with it. Michael taught me about making your best judgment, being wrong, making your next best judgment, being wrong, making your third best judgment, and then doubling your money.
"Die Kunst des Schreibens besteht darin, die Welt so zu beschreiben, wie sie ist, und gleichzeitig so, wie sie sein könnte."