These two are both as old as the hills and well known to people who read sales manuals as the "door in the face" and "foot in the door" techniques respectively.

These two are both as old as the hills and well known to people who read sales manuals as the "door in the face" and "foot in the door" techniques respectively. https://en.wikipedia.org/wiki/Door-in-the-face_technique https://en.wikipedia.org/wiki/Door-in-the-face_technique