According to F4WOnline.com, Batista, as well as other WWE superstars, are currently upset with money and pay in the company.
PWInsider.com previously reported that Batista did not want to do the job to Daniel Bryan at Payback, but F4WOnline reports the situation is more Batista being frustrated that financially, things are panning out differently than what he was told when he agreed to return to WWE. It's being said the money isn't that great right now, and when you have the kind of money Batista has, it makes it that much easier to walk away from WWE, much like CM Punk did.
With regards to Batista taking time off, he was scheduled to take time off in June anyways, so he decided to make an earlier exit. WWE officials spent most of Sunday trying to convince Batista to stick around and work Payback, but word as of a few hours before his Extreme Rules match is that "things are not looking good" in terms of Batista sticking around.