Most Helpful Opinion
A non symmetrical appearance is considered ugly, for physical appearance. I mean one side of the face/teeth/legs/boobs you name it, not looking similar to the other one. Like if someone has one eye that can fully open and the other that can't because they have too much eyelid or something. It creates a weird and confusing kind of look that drives most people away, and puts most people off too.
People who have a massive amount of non-symmetrical features get considered ugly. Those who don't are generally considered normal, and those lucky enough to be able to hide the flaws or indeed, have none at all, are considered beautiful, handsome, or smoking hot, depending on your opinion.
Love always override those minor flaws, as well.
Personality relates to anyone who has strong emotional ties to the more negative side of emotions, such as fear, anger, sadness and that sort of thing. Someone who gets angry quick and fast and lets the anger control their actions would be considered ugly, as well. Spiteful and nasty people are also considered ugly on the inside, because they have a more negative and mean outlook on life and other people - not fun to be with most of the time.
My opinions anyway. I hope this helps you. :)