#4 Alberto Del Rio
Alberto Del Rio is probably one wrestler that WWE regrets hiring because of everything that went on with him outside the ring. One of the great performers in the ring, Del Rio was deservedly pushed by the WWE, but slowly and steadily his actions outside the ring started taking center stage.
Reports came out of Alberto Del Rio's alcohol addiction and his erratic behavior in the backstage area. After that, reports came out of his abusive behavior directed towards his girlfriend Paige (the current GM of SmackDown). All these things slowly led to the killing of Del Rio's push and departure from the WWE.
It does look like WWE have seen the last of him but when it is WWE you can never be sure about what they do next.