Somebody wrote:

What exactly is the point in going through all this rigamarole? Some jerk
calls that you don't want to talk to -- how hard is it to just hang up the
phone? Why do you need to make him hang up?

CONTROL!

The SOB makes the decision do so something that is counterproductive at
best, a most unpleasant task, which is the point of the exercise.

Basic Psychology 101.

Lew