The Clown Effect in Sci-Fi

Bad guys usually start off pretty badass and you're scared of them, but then once you get used to them, they turn into almost like clowns. I mean, Thanos is a good bad guy. He doesn't become more clowny, I think. So, okay, so sci-fi, all right, fine. What about alien though? I'm just the alien. The alien from aliens and like, you know what I mean? Well, here's the question I've got to ask about the alien. It's just an animal. Like it would be like being angry at a dog, like Koo-Joo from the film Koo- Joo. You