Judging others is never justified especially when you barely know the person.
Before judging others, what you must do is to be able to understand, to know what their story is.
After all, each person has his own story to tell, his own personality to measure up to your scale.
Always keep in mind not to be judging others unless you want the same to be done unto you.
Well, in case you are still confused and profound, here are some quotes about judging others to help you out.