One of the invisible forces that drives our culture, our lives, and our actions is the beauty imperative. Put simply: women are required to be beautiful. It is not acceptable to be unattractive. It is also not acceptable to be physically attractive, but to refuse to take steps to be beautiful. (Witness the shame heaped upon beautiful female celebrities who dare leave their homes without makeup, or in unattractive but comfortable clothing.)
The worst thing, of course, is to be unattractive AND to refuse to take steps to be beautiful. Women are expected to constantly apologize for not being more beautiful, while at the same time spending hours every week - and thousands of dollars a year - on their beauty regimens. (This is similar to the thing where you spend all day cleaning your house, and when your dinner guests arrive, you apologize that it's "such a mess.")
And heaven help you if you are both fat and unapologetic about it!
All women know the things they "ought" to be doing to maintain their appearance. Work out, lose weight, pluck your eyebrows, have your hair cut regularly, make your hair do the opposite thing (if you have straight hair, you must curl it. If you have curly hair, you must straighten it), wear lipstick and mascara and concealer and probably an under-eye concealer for good measure, moisturize, trim your nails, wear nice shoes, wear a nice dress or a nice shirt and pants. And that's all before we get to the list of things women "ought" to be doing for others, like house work and being demure!
We rarely question the beauty imperative, perhaps because it is so effectively being sold to us. (The Professor, What If...? blog asks, "What if the beauty imperative wasn't so profitable?") Dove wants you to do something about your unattractive armpits. Latisse wants you to fix that thing where your eyelashes are too sparse. Where does it end? It doesn't.
Every woman draws her line somewhere. But the very fact that we have to draw a line is symptomatic of a larger problem. You have to wear lipstick: says who? You can't just let your hair lie there: says who?
The beauty imperative is also a function of the fact that in Western culture, women's bodies are public property. We are subject to public scrutiny and public shaming to an extent that men are not. The public feels that it has a vote on what we do, say, wear. (This is, after all, the entire raison d'etre of the gossip magazines. How often are male celebrities photographed at the beach and slapped on the cover of a magazine with the headline "CELLULITE!"?)