Occams razor.
Let us hypothetically consider how one might engage in enough voter fraud to sway the election via absentee votes as Trumpers alleged that it was done.
Firstly you would have to have thousands of addresses. No that would be too big, messy, expensive and too hard to conceal.
Okay, you could maybe steal all the applications but what if the real people voted? So it would have to be dead people or those you knew for sure definitely would not be voting. The trouble with that one is again it is too easy to be found out. It is true that Right-wing news organisations and Trump's team have published lists of dead people voting but guess what? They turned out to be alive.
You could do it at registration but for that would need some people in the post office to divert all the registration letters. What if those unregistered voters decided to register?. I mean there were lots of drives to register.
Then you would certainly have to have lots of your guys on the inside? I mean you couldn't pull a job like that without them. It couldn't be Dems, too obvious. it would have to be Reps but how could you know that they wouldn't double-cross you or be undercover?
Then you gotta have premises to work in, okay that parts not too hard but all those different people coming going because you would have to have lots of different signatures.
And what about your crew? Can you imagine the number of different signatures you would need, let alone all the pens? How do you keep them sweet till January with Guilinani offering 100 grand for snitches?