A work comes out and either flops or is a massive hit. But a Vocal Minority has the opposite opinion. They love the flop or hate the hit. And the don't stop expressing this counter opinion, especially to people that enter their Fandom. Then eventually this counter opinion comes to be accepted as the real history. The flop is presented as a massive mainstream hit, that was just put down by those who didn't understand. The hit is presented as a bomb that caused a massive backlash. Now any decent look at the facts available at the time show that this isn't the case, but this image can strongly persist. Furthermore, if those working in the medium of said flop/hit believe this image as well, they can make other works fit what the vocal minority preferred, even though it's still against what the mainstream likes. This can lead to some trouble down the line. Not sure if this should have examples, but this is an audience reaction I've noted, so it falls under the audience reaction tropes (and thus would be on the YMMV pages for any work).
Hello, Unknown Troper. You'll need to get known to lend a hand here.