#4. Safety
We talked about the better pay on the previous page. What accompanies the good paycheque is the safer work environment in WWE.
While most of the independent promotions rely on bloody spots and unsafe hardcore actions, WWE nowadays promotes bloody spots very sporadically. Chair shots to the head are banned and most spots involving impact to the head are rarely used.
The combination of safer matches and better pay is one of the biggest reasons why WWE is still one of the most sought-after wrestling promotions in the world.
#3. The contract
WWE is hell-bent on signing Kenny Omega. Thus they are going all out on the Cleaner to convince him to join WWE.
According to various sources, WWE is offering Omega multi-million dollar contract with various perks. This may involve creative control to an extent and title runs.
Wrestling Observer's Dave Meltzer told that WWE had made Omega a "fantastic" offer. Even though the specifics of the contract is not yet revealed, one can assume that it would be enormous.