It can depend on the player and the position.
As an example, in our school we have a 6'5 lefty first baseman. He has an average arm, and no foot speed. However he is excellent defensively and swings a mean bat. This kid is never going to be anything other than a first baseman.
It's easier for righties to move around, but even at that a kid may be a good third baseman, but lack the footspeed to play short or second.
Looking at a college scenario, a kid may be a great catcher - but barely average at any other position. If his college all of a sudden lands a stud commit or two at his position, he faces being a backup at every position he can play. That's not a real tempting scenario.
Ultimately that's why I say you need to love the school you commit to, regardless if you ever put on the uniform or not. It's not just a baseball decision, it's a life decision. Always ask, would I be okay with this school if I got cut or injured? If the answer is no - you better be real sure about the baseball situation.