Ultimately, it's about OTHER WOMEN. Women are innately in competition for the most desirable men. It makes sense therefore, that women will want to make themselves more attractive to men than other women. It is ENTIRELY a case of outdoing the other women. Women therefore dress to impress and compete with other women, not necessarily to impress men. A perfect example: when a woman receives a compliment on her clothes (essentially her complete "ensemble") from another woman, it is far more consequential or significant, than if it came from a man.