Denis Kang, Rameau Thierry Sokoudjou, Gerald Harris, Houston Alexander, Brandon Vera and now Jimy Hettes and Charles Oliveira.
All of these men (and far too many others to list) were once considered next big things or were indisputably the heir-apparents to their respective weight-class titles. Of course, none of them lived up to expectations.
They were all exposed at one time or another for what they were—mortal, human.
The problem with these fighters, or at least most of them, wasn't that they were bad fighters, it was just that MMA fans (and in some cases UFC marketing) hyped the fighter up to such a degree that nothing they could do in the Octagon, save for a Mortal Kombat-esque "Brutality" finish, could fulfill all the prophecies that were made.
Sokoudjou was supposed to be the greatest light heavyweight in the world but he had fewer than 10 fights; Brandon Vera was fated to be both the UFC light heavyweight and heavyweight champ.
Just so, UFC 152 combatants Charles Oliveira and Jimy Hettes were supposed to be the future in their divisions.
Oliveira's Jiu-Jitsu prowess was supposed to carry him to the top, yet after his recent loss to Cub Swanson, he's only 2-3 (1 NC) in his last six.
Hettes ran through yet another man who deserves to go on the list of overhyped prospects—Alex "Bruce Leroy" Caceres. Hettes then embarrassed a proven commodity in Nam Phan.
So strong was the Hettes hype that his match against Marcus Brimage was supposed to resemble something along the lines of a pro-wrestling squash match (the Undertaker vs. random jobbers comes to mind).
However, Brimage made Hettes look, well, like a young, inexperienced fighter who hasn't been tested yet—and that's what Hettes has been the whole time, but nobody realized it due to the hype machine.
Hype is a dangerous thing. It gets fans to think fighters are nearing godliness. Then, when the hyped fighter loses, he suffers a tremendous decrease in popularity that he likely never recovers from.
Therefore, it'd be best if MMA fans (and pundits) just toned it down regarding the hyping of fighters; the future of the sport's young stars depends on it.