I agree with the people saying he didn’t really plan or expect to win, but I think you have to at least balance that with the fact that becoming president brought him more fame, more power, the adoration of millions of (disgusting) people, new avenues for bilking people out of their money, etc. No matter what the price that’s gone along with it, I don’t see any possibility that he regrets running/winning. As always, he just blames other people for anything bad that came from it