Beauty is hard to quantify and although there are objective standards for that as well, I think its mainly subjective.
This seems to be the exact opposite of what you originally said? There's lots of art where the main goal is to create beauty, if beauty is mainly subjective, then judging that art is going to be overwhelmingly subjective as well.
If you try really hard to make something beautiful, put in a lot of time and effort and there's a lot of "complexity, the skill required, the originality, and the ability" and make something that isn't subjectively beautiful, then it's not good art.
If someone just whips up something without much skill or complexity, but makes something that people find subjectively beautiful, then that's good art.
Somehow you've got to reconcile these three facts: