A convincing heel always needs a germ of truth to guide (and often explain) their heinous actions. The majority of failed heel turns dont work because the bad guy has no apparent motivation for doing what he/she does. In his ECW days, Mick Foleys Cactus Jack persona turned heel because of the infamous Cane Dewey sign (for those not in the know, one hardcore fan was jokingly suggesting that Mick cane his infant son for the amusement of the ECW crowd). This sick joke (something that genuinely upset dedicated family man Foley) became a springboard for his character to turn against the bloodthirsty ECW crowds. He did so via his real life feelings of frustration towards them and those feelings came pouring out in his sterling promo work/matches. By my reckoning, John Cena has more than enough motivation to turn heel. As a Human being, he is an exceptionally nice person, he puts in enough hours for charity for it to qualify as a full-time job and he has sacrificed much for the WWE and its fanbase over the years. Yet still, they hate him. He gives them everything, and it is never enough. He undergoes surgery and then rushes physiotherapy so he can get back and perform for them again, yet still they boo and taunt him mercilessly. He fights fair, shakes hands after a match and laughs off their derisive chants and constant putdowns, but they just carry on regardless. Put simply, it has to hurt. Bray Wyatt is right. They dont love you anymore, John. WWE fans have made fun of Cenas painful divorce; they made (and continue to make) jokes about his (admittedly limited), repertoire in the ring. They laugh cruelly at his relationship with the younger fans. Go to Google Images and type in John Cena Meme the angry heel promos practically write themselves.