I 100 % believe that 80 % of the population is in the wrong bra size . For many reasons as you point out . Selection choices , companies measuring wrong , salespeople pushing the wrong size and fit to make a sale . There are options out there , but for the majority of them , it is an online option . Like our clothes . pI feel so sorry when I see a lady out in the wild wearing the wrong size with boob spilling out everywhere . Also most people don ' t understand that a DD cup isn ' t a static volume . A 32 DD is going to be a smaller volume than say a 40 DD because the base is broader to get the 5 of breast projection on a 40 band . Most people would guess that I ' m a DD maybe a DDD , even though because of my height and proportions that is not even close to accurate . TLDR Emphatic agreement with your post .