the Zeigarnik effect, after Bluma Zeigarnik,

When you leave a Task unfinished and move quickly onto something else, you leave part of your attention behind you, stuck to that project you were just working on. University of Minnesota professor Sophie Leroy, PhD, calls this “attention residue.”

Cialdini says that he harnesses the Zeigarnik effect himself in that he deliberately finishes writing before he’s ready. Finishing early, in mid-sentence and when you really want to keep going – is a tactic writers can use to help them keep focussed so they come back to the writing feeling motivated,