Even Trump had no idea that he would win in 2016. He actually thought he would just inherit Obama's cabinet. That's how unprepared and clueless he was. Melania stayed home for how many months waiting to hear that it was just a practical joke that they were pulling on it.
Meanwhile, Hillary was sitting on $40,000 worth of fireworks set to go off in celebration of her win, and of course they didn't.
But once they realized Trump just didn't give a crap, that he would just push and push hoping things would go his way, and if they didn't, he just move on to something else, they decided to utilize him. What better way to expand and centralize the powers of the government and the presidency than with somebody who had no clue what the limits were.
Nixon, Reagan, W Bush... they had limits because they were worried about the consequences. Trump has no idea that there is such a thing as consequences. He just takes it personally, takes it as a personal attack, and keeps going for it. He's there stooge, the two they've been waiting for.