What do you think may be a reason why I thought for many years growing up any person who was ugly looking must also have a bad personality?

I know not everyone is going to think I’m pretty or I even may be unattractive to some people but anyway back to my question.

I’m honestly not making up excuses but for years growing up I truly believed anybody who I thought was ugly looking must also have a bad personality or be a bad person and it would be good for me if I didn’t try to be friends with them and I should stay away from them.

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I never imagined this about the people I thought were plain looking and good looking though.
What do you think may be a reason why I thought for many years growing up any person who was ugly looking must also have a bad personality?
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