Hulk Hogan trying to take Bret's momentum and making Yokozuna do the job to become WWF Champion at WM 9 when at the time when WWF needed to move into a new era and pretty much making WWE do a do-over the following year.

Or

Shawn Michaels making Vader job to him at Summerslam 96 and acting like a douchebag through out the make. IE telling Vader to "Fucking Move". and Pretty much killing all chances of having Vader be a big monster for WWF and just ended up being a jobber.

Hogan, but Shawn's antics against Bret were worse than Hogan's.