Trump allows his ego to make things much more difficult for himself than need be. If Trump changes after being sworn in he will likely complete his term.
If Trump continues to let his ego pick needless fights, and continues to be vengeful, and continues to be greedy and continues to put himself before the country, he wont last his term.
Trump is a lot like GWB Jr. Trump and GWB Jr are rich boys that never needed for anything, part of the 1% born and bred, and just being the figurehead of the party letting their VP's do all the work.
Trump is different than GWB Jr. in more important negative ways that can't be reconciled when he's POTUS. Greed, ego, self first, multiple personalities, siding with the enemy & attacking the integrity of our national intelligence agencies.
You never know which Trump is going to make the final decision on ANYTHING, and others in power are going to tire of that very quickly!