The Donald is a narcissist--nothing new, but he wants all the attention. He is vindictive—nothing new, but it is immediate, and no slight goes unchallenged. This type of personality is common enough in the working world, but so starkly naked it doesn't often appear in respectable circles. This sort of bully exists only in security, he gets away with this behaviour because he has the latitude to do so. It is self-confirming, and grows. Normal people suffer this sort of obnoxious fool, because they have to.
Trump is a businessman. He will say anything at the moment to work towards what he wants. If some are gullible to believe, it is on them. Trump likes to win, and call others 'losers'. Losers do not win, they can get stiffed, and come out with nothing. Trump can withhold money, and send lawyers instead. I have seen contractors do the same. They often cheat their employees, whom will live with being cheated to keep employment. Some contractors cheat everyone. Each time a cheat gets by undetected, and unchallenged—it is a win, it is profit. If he does not win directly, his lawyers will do the winning for him. If something fails disastrously, file bankruptcy and pay nothing—win, repeat. Trump repeats a lot. Hey, he is a businessman. When fools say a businessman is needed for office, do not be surprised to get a ruthless egotist. Hey, it's business.
I as a d/Democrat will enjoy the losses Trump will bring. Where are the Republicans for Hillary Clinton?