We always try to judge people by their appearance. At the first sight we always make a categorization according to different criteria if we like the person or not. Everyone of has detains some standards we apply on practice for the person we like to analyse.
We communicate with each other. We also communicate on our side and try to believe that we have been understood on the other side as well. Many of us also think that they have also abilities in this sense. We cannot perceive thinking that we have said someting the other maybe understood the contrary of what we intended to say.