Le’Veon Bell
Bell was excellent during his time with the Pittsburgh Steelers but he destroyed his career. He emerged as one of the NFL’s most exciting players but he grossly overestimated his value. He sat out for a full season in his prime because he thought he could make more money elseshwere. This was a career-defining mistake as Pittsburgh shrugged their shoulders.
Then he paid for his mistake because he went to the Jets. Their neew head coach Adam Gase was a disaster and failed to get the best out of Bell. After a couple of seasons, Bell managed to wrangle a move to the Kansas City Chiefs. But he failed to make much of an impact for the Super Bowl contenders (via SBNation).