It will come as no surprise to find Chael Sonnen on a list of this variety, so best to get him out of the way early.
In 2010, The Bad Guy was embroiled in a highly anticipated clash with one of the titans of the sport, Anderson Silva.
Instead of shaking hands and agreeing to let the better man win, Sonnen took it upon himself to (attempt to) burrow under the skin of the Brazilian.
Coming out with arrogant remarks such as threatening to 'drag Anderson Silva out of a hotel and beat him up anytime (he) wants' and claiming he was 'the toughest guy in the company, period' Sonnen had put himself on quite the pedestal en route to UFC 117.
In the end, Silva submitted Sonnen in the Fight of the Year winner.
However, The Bad Guy clearly hadn't learned from his mistakes and waxed lyrically about how the two's 'skills were not even close', on the road to their rematch at UFC 148. Sonnen would lose that bout, too.
Sonnen hasn't been sighted outside of any of Silva's hotel rooms since and it's probably wise for him to keep it that way.