The fundamental attribution error was discovered by Social Psychologist when systematically studying how people explain the behavior of others (Ross, 1977; Ross et al., 1977). We tend to overestimate the influence of internal factors and underestimate external factors. We are more apt to judge the other as rude or unaware (internal factors) than caught off guard by a confusing or unclear question (external factor). That is how we see things when we are judging others. It is different when we evaluate ourselves
«My university students are quick to judge me as being an extrovert, outgoing and sociable.
When I lecture in large classes of 600 to 800 students I am animated and enthused, and they attribute my performance to internal personality traits, but I know better. I see myself in many different situations and realize just how much my behavior changes depending on where I am. In many social settings I am downright shy and reserved. I am very sensitive to external influences»