#4 JBL
If you were a fan of the WWE during the Attitude Era, you will remember JBL as part of the APA where he teamed with Ron Simmons as Bradshaw. The APA was a successful tag team and JBL didn't quite need the character makeover which he ended up getting.
However, as it would turn out, the character transformation was one of the best things which ended up happening to his career as a solo performer and would lead him to become one of the biggest names in the business.
He shed the APA gimmick and turned into a rich arrogant businessman who sought to berate others and benefit himself. This character was a superb heel and easily became one of the most hated but popular characters within the WWE.
JBL went on to become one of the longest reigning champions in WWE history and this was something which would have never happened under his Bradshaw persona.