Because they kept talking about it like there was a plan, trump said people won't have to vote again, musk kept bragging about how the machines could be rigged, the momentum was with kamala for sure, its something trump would do. Especially project and then do the thing hes accusing others of, we saw him refute fair elections, and we see him rigging the midterms right now. Also his rhetoric changed at some point. Early campaign he was all abput things like "black jobs" trying to get swing votes in his campaign. Then after kamala became his opponent, it switch we d at some point to things like "they're eating our cats and dogs" he stipped trying to get swing voters, and instead focused on radicalizing the voters he already had. They've all but admitted it. Oh, also his complete victory in all swing states. No chance that was a fair election.