Okay why are anime Girls so clumsy

What is going on? She is usually so sure-footed and then she turns into clumsy Carrie the next? I mean like I'm clumsy but I never fall down because of nothing. It's usually more like running into door frames and dropping things and caring fluids that always seem to spill and also tripping over nothing at all but that's not like, from average walking, that's like from not wearing glasses. Are all anime girls need glasses? I mean like I lose my glasses and I trip over everything, is this what they're telling us? That everyone here is nearsighted?