College football recruiting has become such a huge industry, it's easy to get sucked into the hype. Even if you don't, a lot of times players will begin to believe their own before they accomplish anything.
That's led to a high number of early transfers, and while there are plenty of exceptional young players who burst onto the scene each year, there are five who don't live up to massive expectations for every one who does.
Sometimes, there are simply too many headlines early on, and players' ceilings are exaggerated or fans' hopes are unrealistic. Most often, it just takes a while for younger players to adapt to college ball.