Until you know how to focus, you’ll never be able to think clearly, solve problems, make decisions, or remember things. Being focused is important but staying on a task is becoming harder and harder. A symphony of notifications can draw you out of whatever you’re doing at a moment’s notice.

Source: How to Focus and Maximize Your Productivity (the Definitive Guide

I hate to be interrupted, but I didn’t realize what other factors were affecting my concentration and focus. Especially how important exercise is!