Alot of times we pre judge people without actually knowing them. For example: people may think an attractive man or woman may be arrogant or snobbish based off of their physical appearance.
It is wrong to judge a person based off of their appearance. We all have our own internal & external struggles we are all individually facing.
Most of the time the judgements or perceptions we create of other people are actually our own insecurities. Be open to learning, and accepting people as they are.