The Zeigarnik Effect is our tendency to remember incomplete or interrupted tasks easier than completed tasks, and it reveals a great deal about how memory works. Named after Soviet psychologist Bluma Zeigarnik, he was the one who first suggested that failing to complete a task creates underlying cognitive tension. 

This results in greater mental effort in order to keep the task at the forefront of awareness. Once completed, the mind is then able to let go of these efforts. We can thus use this to our advantage, by simply addressing what is on top of our mind in terms of unfinished work and get it done quickly for relief.

But there’s a downside to this as well. Each incomplete task divides our focus, making it harder to concentrate on what is in front of us. Even if we physically disconnect from work, unfinished tasks filter through to our vacation, weekend or sleep. A way out? Simply get tasks done immediately so nothing gets logged in our memory after we leave the office or complete our time at work.

Unfinished work continues to exert an influence, even when we try to move on to other things. When we start working on something but do not finish it, thoughts of the unfinished work continue to pop into our mind even when we’ve moved on to other things. Such thoughts urge us to go back and finish it.

If anything, the Zeigarnik Effect is both a boon and a bane to our productivity. We start by taking the first step, no matter how small on our tasks. Once we've begun—but not finished—our work, we will find ourself thinking of the task until, at last, we finish it. To avoid it, just note down everything we need to do next, and then act accordingly.