I'll answer that for you
You see, voting is a moral choice. A choice to show the world I am not going to stand for the same corruption, the same Washington BS that goes on every day. I can't morally vote for someone who I feel is lying all the time, so I need to vote with my own sake and show everyone I am not going to stand for it anymore.
Forget that "voting for my morals" or "voting ethically" means that I'm actually standing on the sidelines as the GOP nominee talks about mass deportations, hangs around with neo-nazis, embraces his entire base of racist dump people, or even worst, smart racists. I could try and stop what could very well be the collapse of the world economy under a Trump presidency, I could prevent the SCOTUS from going conservative for another generation, but I have to vote for my morals!