Why is Mariah Carey underrated in the "Hip-Hop" world?

I'm not sure, but I should think it's simply because she isn't famous for doing hip-hop. She began her career by singing pop, or at least that's what made her famous in the first place. I don't think people in general even know that she has done that much hip-hop at all. That's why I think she s being underrated as a hip-hopper, or whatever you wanna call it :)