Why do some great movies still get low IMDb ratings?

I’ve noticed that a lot of amazing movies — both in terms of story and performances — sometimes end up with surprisingly low IMDb ratings. For example, a few recent films that critics loved didn’t perform that well here. What factors actually influence IMDb ratings the most? Is it mainly early audience reactions, fan bias, or the number of votes from different regions? I’d love to understand how ratings stabilize over time and whether they truly reflect a movie’s overall quality.