In your opinion, do the young stars and starlets in Hollywood schedule their train wrecks?

I've noticed a pattern in their devolving persona's whereby they seem never to be in crisis at the same time as each other. Do they really have people who manage their careers to this point? I've heard that their are, yet am left wondering. Doesn't seem to have worked well for Lindsay Lohan if this is true, as I would imagine not many insurance companies would cover her for a movie. Also, if Hollywood is that corrupt, I fail to see how Charlie Sheen's last episode served him except - unless - he wanted out of a contract making 2 1/2 men. Just pondering, and really hoping to hear some opinions on this subject.