answer:Dude, this is, like, the third time you’ve asked this question. I have tiny A cup boobs but even for me it hurts to walk up and down stairs or to run without a bra due to boob bounce-age. I can only imagine what it’s like for women with large breasts. Bras also distribute the weight of the breasts over the body which helps prevent some of the back problems that women with large breasts are susceptible too. Also, regardless of whether it’s a good or a bad thing, cultural norm right now is to not have imprints of your nipples visible through your shirt. Bras also prevent this. Not wearing a bra could, in this regard, lead to women getting passed over for job opportunities, etc. because it is currently considered unprofessional or rude to show nipple dimples.