Judging Me, Judging You

Many humans attach meaning to anything about others, and the less mature a person is, the more they believe that they're CORRECT. So each person thinks that your hair means a certain thing about you. your clothing means a certain thing about you, your car, your height, your sex, your face, your makeup or lack thereof, your facial expression, etc. Even more importantly, they judge YOU on how your speech and manner makes THEM FEEL, and tend to attribute ALL of the way you "make them feel" on YOU, not themselves. (In other words, if they find you attractive and you acknowledge them or are nice to them, they'll say you're a "great guy!" If they find you attractive and you don't give them enough positive attention because you didn't hear them or you were working, they might say you're "stuck up", or perhaps that you're a "very hard worker", depending on the individual. If you're smaller than they are, they will assess everything you do and say in a different way than if you're bigger than they are. If they find you attractive and you're a woman, they tend to crank up the volume on their "judgment" dial to "High", so they attribute much more meaning, negative or positive, to anything you say and do. If they see you as very unattractive (to them), they tend to do the same.)
If and when a person learns a little bit about you personally, then they tend to believe their own assessments about you based on your interests, job, financial status, your apparent ancestry, your Facebook posts, the people you are Facebook friends with, your partner, and your political affiliation or lack thereof.
Then, they will attribute even more meaning to the way your actions "make them feel", so if you bring them cookies or send a card, they tend to see you as a wonderful person, no matter what you're really like. If you don't go out of your way to "make them feel special" or give them extra attention, depending on the maturity level of the individual, they may tend to judge you as "self-centered" and "uncaring", regardless of anything real about you, your life, or your real actions, experiences, and personality.
The less mature the person is, the more they will treat you according to the way they have assessed you in their imagination.
(Very few will bother to spend any time or effort actually finding out real information about you, your life, your past, or your real personality, and even those who do can't make an accurate picture; it's not possible for them to gather all of the data about you that exists, or process it accurately, nor you them. There will always be huge missing chunks of data no matter who is doing the information gathering, and there is no objectively reliable source to gather it FROM in the first place, so the exercise of gathering information about a human being cannot result in hard scientific data.)