It's a talent, so it's something given to someone, and not earned, but it can be cultivated or wasted.

Female beauty, like male strength, peaks around peak fertility, so they're clearly meant to facilitate childbearing, through marriage.

But even waning female beauty has an uplifting and inspiring effect on everyone who beholds it, and that should be used for good. Female grace and elegance is also a talent and you can have that for a long time.