#2 Buff Bagwell

The WWE have often said how WCW didn't create any original stars, and whilst the now-defunct company did often rely on former WWF talent, one star they certainly created for themselves was Buff Bagwell.
Originally a clean-cut babyface, Bagwell later became a cocky heel and could have been a big star when WCW was bought by the WWF in 2001.
In his only WWF televised match though, Bagwell had an awful match with Booker T, a match so bad it reportedly killed off any belief the WWF had in WCW being its own brand.
Bagwell's mother, (who somehow is a former WCW Tag Team Champion) reportedly called in sick for her son when he was unable to make a live event, and whilst Buff has denied this claim, being such a mama's boy has been frowned upon by WWE.