I recently watched the Lindsay Lohan movie Confessions of a Teenage Drama Queen on TV. Like a lot of Hollywood movies, it has a message that goes something like: "just believe in yourself, no matter what anyone else says, and eventually you'll triumph." That is a sweet sentiment, but in many ways it is often bad advice. For example, when everyone else begs you to stop working on your perpetual motion machine and do something useful for a change, maybe you should listen. Only paying attention to one's own ideas and ignoring all feedback from the outside world is a bad strategy.
In the recent American Idol open auditions, many of the first-round rejects walked away saying that the judges were completely wrong. They vowed to keep following their dreams and become pop stars. For a tone-deaf singer, this is just a terrible waste of their time. The sooner they quit singing and find something else they are more suited to, the better.