While there are some women who do not wear undergarments at all, the majority of women do. For the majority of women that wear undergarments, they want their underwear to fit. The perfect fit is very difficult to find. You will see panty lines that indicate the panties have worked it's way up into the buttocks. This is not a good fit. With so many different styles available in womens lingerie, sizes may vary for certain styles. In panties, you have boy shorts, bikinis, briefs and thongs. A good fit is hard when you have to choose from S, M, L and XL. With numbers such as size 5, 6, 7 and so on, I seem to get a better fit.