The reason most of us go to work is to earn money. Pro wrestlers are no different, they have a passion for what they do, but it is still a job to them. CM Punk especially saw pro wrestling as a job. It was a career that involved only about 30 minutes a week of what he actually enjoyed doing (the pro wrestling part). Aside from that the WWE job was mostly a pain in his a**. Long hours, arduous travelling, tiresome meet and greets with people he had no interest in.... it was hardly grumpy Phil Brooks' ideal vocation. Having been under a WWE deal from 2005 to 2014, Punk had finally earned enough money to do away with the hassle. The few years he had spent as a main eventer had in particular set him for life - he's easily a multi millionaire. As such, Punk felt he didn't need WWE any more. His current thought process is 'why should I go back?'. He doesn't need the hassle and he doesn't need the money. Well, he thinks he doesn't need the money. In twenty years time if Triple H came calling with a Bruno Sammartino level offer, how could Punk refuse? He thinks he can afford never to go back, but eventually, money often talks. Especially if wrestling history is anything to go off.