What are bad/terrible/horrible characters that you acknowledge are well-written and understand their actions, but you're confused by the contrast in the fandom, where they praise them as if they're good people or have done the right things?

For context, I'm referring to characters whose actions, while morally questionable, are well-developed and justified within the narrative. However, it’s perplexing when the fandom overlooks these flaws and praises these characters as if they’ve done the right thing, despite the clear negative consequences of their actions. I mean, you can LOVE them because they're well-written while acknowledge how bad their actions are, but do you ever disagree with how the fandom perceives them?

Edit: It's not a crime to love them because you appreciate their writing. Take Darth Vader, for example. You know all the terrible things he's done, but you still love him because he's such an iconic villain in history.