Ric Flair in the 90's. They had a ready made feud with Hogan and it went nowhere because of "failed matches on the house shows" so instead he gets Savage. Not bad matches but they weren't greats. He only lasted just a year and a half but could have done much more.
Kofi Kingston in 2009. He had the Steamboat Mania III fire with his Orton feud and then what happens, nothing and he has not been in the same spot ever since.
Owen Hart in 1997. Sure we all knew Austin was going to be the star by mid 97 but Owen after the Montreal Screwjob had a big crowd reaction but then WWF Orton'd him before Ortoning was cool.