Trump’s attacks on vote counts seem to follow an authoritarian playbook - The Washington Post

“The Russian mentality is, ‘Whatever truth works for you in that moment is the truth you embrace in that moment,’ ” Farkas said. “Even if you say something different two minutes later, it doesn’t matter. You call on that second truth for your immediate need, and your followers don’t care.”

This is the most succinct explanation of Trump’s behaviour that I have seen.