The title of this post leads to a wonderful article on "self-esteem." Self-esteem is not the end all and be all of improvement in human behavior and success. In fact, it may be just the thing to perpetuate bad habits and failure. In essence, if someone is screwing up, what's the basis for self esteem? Complementing mediocrity perpetuates mediocrity.
The link is a must read for anyone interested in this topic.