<P> Foot - in - the - door (FITD) technique is a compliance tactic that involves getting a person to agree to a large request by first setting them up by having that person agree to a modest request . The foot - in - the - door technique succeeds owing to a basic human reality that social scientists call "successive approximations". Essentially, the more a subject goes along with small requests or commitments, the more likely that subject is to continue in a desired direction of attitude or behavioral change and feel obligated to go along with larger requests . FITD works by first getting a small "yes" and then getting an even bigger "yes". </P> <P> The principle involved is that a small agreement creates a bond between the requester and the requestee . Even though the requestee may only have agreed to a trivial request out of politeness, this forms a bond which--when the requestee attempts to justify the decision to themselves--may be mistaken for a genuine affinity with the requester, or an interest in the subject of the request . When a future request is made, the requestee will feel obliged to act consistently with the earlier one . </P>

Who discovered the foot in the door phenomenon