Genetics obviously but the real shyt is that ALOT of women flat out just don't take care of themselves. People don't realize that you need a substantial level of fitness in you day to day shyt and simply can't be bothered with hitting the gym 5 out of 7 days a week.
But the fact of the matter is that a lot of people are just fukking wimpy and were brought up that way. How many chicks would spend even a hour in the gym lifting heavy (which really makes you strong) and running? They would rather take that hour shopping for all kinds of creams and moisturizers (and clothes) to cover up the
ness. I would bet that 90% of those cosmetics don't do shyt and it's about eating right, working out, not smoking crack/drinking all the time and not getting sick often.