Because they know someone’s gonna come & say ”Shut up, you know you are”. But some girls say they’re not pretty not because they’re looking for attention but because that’s how they feel. They compare themselves & see what others don’t. We see someone beautiful, but they see stretch marks, gut hanging out, small bodily features that wouldn’t catch the average guy’s eye. That’s why some girls can’t take a compliment, they feel like they don’t deserve it.