3 hours a day is just not enough for everyone.

For some projects it's perfectly fine but some tasks can only be done if you focus for a large amount of time on it, work obsessively on it until you reach a milestone.

The greatest work I have ever done, was always done when I retreated like a monk for several weeks, cutting myself of the whole world and working almost non-stop on the task until I made a significant breakthrough.

Then I go back to the livings and share the fruits of my work, and of course, take a well deserved rest for several days.

The trap into most people fall is that they are confusing being active and working.