Heel turns have the ability to completely alter a wrestler's career.
Get them right and a star can quickly become one of the most hated personalities in a company, producing nuclear responses from fans at home and on social media. Get them wrong and you're left with a flailing character that nobody cares about who eventually starts to generate the dreaded 'go home' heat.
In order to create a successful top heel, capable of consistently p*ssing off a crowd whilst equally keeping them engaged, a wrestling villain's motivation has to be as believable/understandable as it is despicable.
For example, many fans know the feeling of being stabbed in the back by someone they thought was a friend, so they instantly understand what the babyface is going through when this happens to them and want the back-stabbing heel to suffer for their actions.
Yet, time and time again WWE have ignored all logic and booked stars to turn their backs on the fans or their pals for the oddest of reasons, which in turn leaves people either not booing or simply not reacting at all to the strange attitude adjustment.