You might think of this chart as the shape of attention. After clicking to start, thousands rapidly exited, some immediately, some after a minute or two. But if you could make it past three minutes, you were more likely to finish than to give up. And once you hit five minutes, your odds of completing the exercise were very high. A quarter who start... See more

Throughout my career I’ve noticed that when I work about 4-5 hours on something, I’m done. Regardless of whether I’ve allocated 6 or 8 or 10 hours to it, I either finish my tasks, or I run out of runway to finish them. Most of the time spent after that is just obsessive tweaking.

This means if you can increase the positive impact of those hours just a little, it will probably have a bigger impact than changes to any other parts of your life.