It’s so bad that my fiancée has some bras that say she’s a B cup and others that says she’s a D cup. In order to go bra shopping, you have to actually try them on to find out if they fit.
If I had to try on underwear to see if they fit, I might not bother with underwear at all!
Agree on all points! When I was had my first grownup job I was trying to build up my wardrobe and found a pair of jeans that fit and felt great. Size 3. I went back after another paycheck to get an identical third pair and when I got home, they were practically falling off of me. I had to exchange them for a 1, which was still larger than the size 3s from just a month or two earlier.
But a fitted bra? One of my best purchases ever. Getting in the right size resolved about 70% of my chronic back pain. Fit is different between bra types but decent brands’ sizes are standardized, regardless what OP says.