If you become attracted to the person, why not? You always have the option to choose the person that you want to date. You should not base your decision merely on how the person looks like. You may have other more valid reasons why you have decided to date the person in the first place.
The person may be the kindest person that you have met. The person may also be the only one who can make you laugh so hard. There is no reason why you should look at only the person’s overall appearance. You will realize that some people will just look better in your eyes as you get to know them more.
This is a question where one would have to look deep inside of themselves in order to answer. First off, if the person was ugly and deemed not to be attractive, is that your preference. If you know what the person looks like and if they are so called ugly, do you accept it. This is all about a question of why you would be into the other person. Do you like them for their looks or do you like them for what they stand for and how they feel inside.
I would not have the frame of mind to think that way when I was looking to date. I would be looking for what they have in their heart. For that reason then yes I would say that it would be a good thing to date someone that is uglier than you. They could be a very good person on the inside and could possibly give you more satisfaction in a relationship than someone who was prettier than you.