People make snap judgments all the time. That woman in the sharp business suit must be intelligent and successful; the driver who just cut me off is a rude jerk.
These instant assessments, when we attribute a person's behavior to innate characteristics rather than external circumstances, happen so frequently that psychologists have a name for them: "fundamental attribution errors." Unable to know every aspect of a stranger's backstory, yet still needing to make a primal designation between friend and foe, we watch for surface cues: expensive pants—friend; aggressive driving—foe.
Via The Learning Factor
Why do businesses evaluate candidates solely on past job performance, failing to consider the job's difficulty? Why do university admissions officers focus on high GPAs, discounting influence of easy grading standards? Investigate the phenomenon of the "fundamental attribution error."