Girl groups, why are they all the rage?

Lately you can't turn a corner without running into a K-pop girl group; be it Girls Generation, 2NE1, 4minute, Brown Eyed Girls, After School, T-ara, Kara, etc. An expert stated "Right now, entertainment has become an industry. Lately, women have been entering more and more into the work field so it is only natural that women have become the focus in the entertainment field as well. Because of women acquiring more power, girl groups in turn have gained more notice. In turn, their popularity will influence the people with things such as fashion and opinions." Early girl groups like S.E.S, Fink.l, Baby V.O.X., Chakra, Jewelry, and Sugar have maintained entertainment life despite the fact that they have all spread out into different fields of the industry. For example, Eugene, Sung Yuri, Ryeo Won, and Yoon Eun Hye have all gone into the acting field while artistes such as Lee Hyori and Ohk Ju Hyun have maintained solo singing careers. Former S.E.S member Bada also mentioned "When I look at girl groups today, it seems like they are debuting in the same environment that I debuted in. I hope that they will be able to maintain sincere friendships while working together." With girl groups being all the rage this year, it kind of looks like the trend is going to continue. In other words, lucky me ;)