Why is the first impression ''always right''?
Most of the times, when we meet a new person we immediately form some kind of an idea/perception of him/her, based on the stereotypes we have about someone's gender, occupation, culture, appearance etc. These stereotypes or preconceptions are called “schemas”. A schema is an organized pattern of thought or behavior that represents some aspect of the world, specifically of the world that we have formed in our minds.
Schemas can be about particular people, social roles, or common events and that is why schemas are part of our everyday life. They help us process information quicker and more efficient in many different ways. First of all, schemas help us process information faster, by drawing inferences from it. For example, people who have watched many times tennis matches see more and absorb more information than people who know little about tennis. As a result, schemas follow the natural contours of the information we receive, because they are suggested by the nature of the information itself. Also, schemas aid automatic inference. This schematic processing happens almost automatically, without any conscious effort. For example, when we meet a rude person, we automatically attribute to him/her other characteristics associated with rudeness, and may be completely unaware that we have done so. Furthermore, schemas add information. They can help us fill in missing information when there are gaps in our knowledge. For example, when we read about the Chinese President, but have no information about his appearance, we imagine that is a man, with slit eyes and small nose.
As a whole, we use schemas so as to make sense of experience quickly. Imagine approaching every situation as if for the first time; it would be impossible to function properly in our everyday lives.