#2 Brock Lesnar wouldn't want to miss out on a lucrative deal and a big WrestleMania payday
Brock Lesnar was a mainstay in WWE for around eight years, following his blockbuster return on the RAW after WrestleMania 28 in 2012, where he confronted and put down John Cena with an F5. He enjoyed a lucrative contract with WWE, which saw him make occasional appearances for a lot of money. Brock Lesnar's mainstream popularity helped him secure one of the sweetest deals in WWE history. There were times when he was absent from the weekly shows on a frequent basis, despite being the top Champion.
Brock Lesnar is bound to earn a lot of money for his WWE return
Brock Lesnar is well aware of his worth when it comes to pro-wrestling. Vince McMahon and company wouldn't want to see him go somewhere else, for a bigger and better contract. All Brock Lesnar needs to do is make a few appearances, starting from the Royal Rumble, all the way to WrestleMania 37, to earn a bunch of huge paydays. It isn't something Lesnar would want to miss, knowing fully well that he wouldn't be asked to make regular appearances on a weekly basis, and he may only wrestle a couple of matches including the Royal Rumble.