Tell you what there often very difficult to loosen up
Not necessarily a bad thing.
I myself like petite girls. Sure, veluptuous girls with big knockers are good eye candy and so on, but they don't really "do" it for me. Smaller girls who have a nice smooth slightly curved figure does it for me.
I don't like to be able to count your ribs, and I don't like to see ribs between your boobs when you wear a cleavage revealing shirt. It's ucky. Like a skeleton with boobs. Not so hot.