Apparently, one of those groups understood the legal opinions[0] around the legal claims made (most of which didn't include fraud at all) and another group believed and promulgated a bunch of lies.

I'm sure that many folks on both sides believed what they were told. However, one group was told something approximating the truth and the other were told bald-faced lies.

[0] https://electioncases.osu.edu/2021/01/summary-of-post-electi...