Men, what is attractive about ass?

I can understand being attracted to someone’s face or boobs, but ass? I genuinely don’t get it.
To me it’s like… that’s where shit comes from 😭. It’s kind of like saying you love the toilet seat. I know the toilet seat itself didn’t do anything wrong, but it’s guilty by association because it’s attached to the toilet 😭.
I’m genuinely not judging-I just want to understand what makes it attractive to you guys.