I don't think it's important to look or even be beautiful. I know I like to make myself look nice if I'm feeling a bit glum or if I'm going out somewhere nice. It's not for other people, it's for myself.
I don't wear make up... Well I wear lipstick and lip gloss but that's it. No foundation, eyeshadow, eyeliner, mascara, nothing. I don't feel the need to, I used to when I was younger and now I look back I think "Urgh I looked awful with make up!" not because the make up was badly done, just because I personally think I look like a transvestite with it and look better without.
The media are always trying to put their distorted image of beauty across to the public and really it's just someone who is really good at Photoshop and a normal person being faffed and played with on there to look "beautiful".
Looking good is a better term I think, if you feel good with the way you look then you look it in my mind. :)