Why is the door in the face technique effective?

Question

Quizplus · Accepted Answer

The door in the face technique is effective because it is related to the norm of reciprocity. This means that when someone makes a large request that is likely to be refused, it creates a sense of obligation to comply with a subsequent smaller request. The person who refused the larger request feels like they owe the requester something and may be more likely to comply with a smaller request as a result.

Why Is the Door in the Face Technique Effective