"Charm is deceitful, and beauty is vain, but a woman who fears the Lord is to be praised." Proverbs 31:30
Too much preoccupation with beauty is vanity and vain! Of course, no one wants to look ugly. On the other hand, nothing is wrong with being beautiful, since God made everything beautiful. The point is what is our attitude towards beauty of a woman?
What is important is how a woman seeks the face of God. It is how she treasure the Lord in her heart! Beauty is secondary only. For when we are obsessed with beauty, it becomes an idol; it's a danger of idolatry.
God does not like idolatry. Therefore, if we love God truly, we have to avoid things that he does not look with favour---and one of these is obsession with beauty and the like.