#6. Dean Ambrose
Dean Ambrose has given WWE notice that he won't be renewing his contract when it's up in April and will be leaving the company after WrestleMania 35 -- something that the WWE confirmed in an official press release sent out to several media outlets.
The unusual situation has people questioning if it's a work or not, but for now I think it's best to consider WWE's press release accurate and true and assume that Ambrose is in fact going to leave.
Naturally people are linking this to similar situations like Kevin Nash and Randy Savage who both announced in advance they were leaving and ended up signing for WCW and said that Ambrose will go to AEW.
But Ambrose hasn't been back in action long after recovering from an arm surgery and nearly dying from an infection. Before that, he was touring consistently for six years and didn't miss a day. So I wouldn't blame him if he just wants a break from the rigorous travelling life that is professional wrestling.