Which gimmick change ruined a wrestler's momentum?

[Keane]

Wrestling history is full of gimmick changes. Some transformed careers, turning midcard wrestlers into legends. Others went badly wrong. A wrestler with momentum, crowd support and a clear character could be handed a new look, a new name or a ridiculous storyline and lose everything they had built in a matter of weeks

Some failures are infamous. The Shockmaster's debut in WCW, when he tripped through a wall and lost his helmet on live television, is still shown on blooper reels. Other examples are more painful, where good wrestlers were stuck with gimmicks that made them impossible to take seriously. Fans often remember these changes long after the wrestler moved on to better things

There is a reverse side too. Some wrestlers survived terrible gimmicks and went on to huge success. Kane started as Isaac Yankem, an evil dentist, and Kevin Nash was briefly Oz, a character based on the Wizard of Oz. The Undertaker was a regular wrestler before becoming the Deadman. So a bad gimmick is not always the end

For me, a painful example is the way The Fiend was handled after his early run. The character was one of the most original things WWE had done in years, and the crowd was hugely invested. But questionable booking, odd finishes and a controversial title loss seemed to drain the momentum. Bray Wyatt was creative and talented, and many fans felt the character never reached its full potential

Which gimmick change ruined a wrestler's momentum? And which wrestler survived a terrible gimmick to become a star?