Why women prefer to wear jeans instead of skirt?.

I know it depends on one’s choice,but nowadays we’ve seen more and more women prefer to wear jeans instead of skirt,I know there’s nothing wrong with that but I’m curious why and how this phenomenon is happening,what’s the difference between wearing jeans and skirt?,is it because new culture,price,or else?,what are the advantages and disadvantages of wearing both thing?,and which one you prefer?.