A task left undone remains undone in two places—at the actual location of the task, and inside your head. Incomplete tasks in your head consume the energy of your attention as they gnaw at your conscience. —Brahma Kumaris
David Allen • Getting Things Done

Can't Stop Thinking About Unfinished Tasks? It's the Zeigarnik Effect
Charlie Gilkeyproductiveflourishing.com

"Much of the stress that people feel doesn't come from having too much to do. It comes from not finishing what they've started."
Leo Babauta • Zen To Done: The Ultimate Simple Productivity System
While the Zeigarnik effect highlighted the tension and memorability of unfinished tasks, Ovsiankina's research delved deeper into the subsequent behaviors this tension fostered. Specifically, her studies demonstrated that when individuals were interrupted during a task and later given free time, they displayed a strong inclination to return to and ... See more