I am slow, so it took until this morning to understand at least the pretense of why some Republicans believe the 2020 election was stolen: few understand how long it takes to count mail-in votes.
The dumb drama of watching states flipped from red to blue created by the media doggedly reporting likely winners of states when no state should have been called at all until the all the votes were counted. Many in the media itself said, given the vast mail-in votes, all reporting should refrain from calling any winner, but just report on the progress of counting the votes. Those pleas when unheard.
I have seen many elections lost by the Democratic challenger where states flipped as the last few votes got counted. I suppose if you had never seen this demoralizing form of failure, you might well believe in a conspiracy.
Of course, none of this applies to the GOP Congressmen and State reps who know better and are fanning seditious lies for political gain. Unclear what pot of gold these characters think they are chasing.