Students asked by a psychologist to tell a lie before discussion groups vastly overestimated how many people in the discussion groups could tell they were lying  Other research has found that when volleyball players perform unusually poorly on the court, teammates notice this far less often than the players expect  Finally, in one research experiment a student wearing a funny T-shirt entered a room full of people
Questioning revealed that only a small fraction of the people in the room noticed the shirt, contrary to the student' s expectations
People tend not to notice the appearance or behavior of others.