Correct me if I'm wrong but I belive it's because he is casting doubt on a system of democracy with almost no real evidence (to be determined). He can challenge it but what is he is doing is saying as if it was fact it was fraudulent without any court case backing. Accusing of a crime with no conviction. He says words like there is fraud not there might be fraud.
He is trying to win no matter what even if it throws out peoples votes which is not democratic.
I'll correct you, you're wrong.
Casting doubt on a system does not mean an overthrow attempt. Are the people supposed to believe without question the way voting systems are run? Sounds like communism to me.
"Almost no real evidence". I guess unless you saw a video of a ballot counter taking say 10,000 ballots marked for Trump and the vid shows that person burning all 10,000, would that be the type of real evidence you're looking for? Or is there doubt because those ballots being burnt could have been received after the deadline, so it wont' matter anyways right?
You need to remove the court system conviction thing a little bit. Here's 1 example of why: Hillary Clinton was a defense attorney and got her rapist client off the hook. Her words were " I knew he did it, but I got the evidence thrown out. Haha".
Courts are not objective like how they should be. Politics are often involved with big decisions.