You know dam* well WHY? The trump will have been ignominiously defeated humiliated crushed shunned reviled smashed smacked down ridiculed mocked. Already mad and terrified he will still have the power to take it out on the world and he will.
Be afraid. Be very afraid. Dread what's yet to come. Unless we experience a DEUS EX MACHINA. We shall be doomed.
It's been said that when Nixon was resigning he spent most of his days sitting in the dark in the Oval Office and he was more or less powerless because aides and millitary personal were told to ignore any crazy orderes that might give. So I think it will be the same with Trump when he gets voted out or resighs and the only damage he will be able to do is destroy the National Treasures in the Oval Office and other parts of the WH. Cheers!