Productivity expert David Allen invented this rule.

Essentially, our mind always keeps unfinished things in focus.

If you have to complete something but you haven’t done it yet, your mind will keep on distracting you. 

It will keep telling you in some way that the work is not done.

So the 2 minute rule says that if you can do something in 2 minutes, do it.

Don’t add it to your to-do list.
Finish it at that time and remove it from your checklist.

You build momentum, reduce your mental load, and sharpen your productivity.