I recently found out a friend that I thought was kind of flat actually had a DD bra size. And then I listened to two women talk about bra sizes for a while.
>cup size is pretty misleading because it's the band-to-cup size rather than sheer boob volume
>some women spend a lot of time looking for bras that fit in specific ways to make their boobs look big (can't imagine spending a bunch of time looking for cups to make my dick look bigger for social capital)
>cup size misconception stems from clothes makers being lazy and women stuffing their tits into standardized bras rather than anything with custom band and cup size