The door test demonstrates that the phenomenon of change blindness is a reality that exists when subjects are outside of the laboratory. Change blindness impacts individuals in the real world. The door test proves this. Subjects were explaining instructions to one participant, and then the presence of the door emerged when a new individual was inserted. The results of the door test show the subjects were susceptible to change blindness: "Even when the perceptual salience of the change was clearly visible, subjects still confidently overestimated their ability to detect changes." The results of the door test prove that selective attention is a reality that encompasses many people in the real world. The mind responds to stimuli in its immediate environment by paying attention to specific details and forgoing others.
The door test demonstrates that selective attention is a part of the mind's response to being barraged with information. Subjects in the door test were unaware of being tested; their selective attention capacity ensured that they would filter samples of information. They were unable to detect the fact that the individual asking for directions had changed. The door test proves that information can be excluded without conscious understanding. Thus the door test demonstrates the presence of selective attention within the individual.