I think my four year old self has said it all!
It does remind me of the quote which hung above the entrance to the art rooms at my secondary school, though.
"In art there are no mistakes, only possibilities."
I think it is one of the phrases I think of most when I am creating, it is so true. No matter what happens when you are creating, never see something as a mistake. When something happens which isn't what you intended, roll with it and work with it - it might just help you create something even more amazing.