" When you’re doing hard work, getting rejected, failing, working it out—this is a dumb time to make a situational decision about whether it’s time for a nap or a day off or a coffee break. Zig Ziglar taught me this twenty years ago. Make your schedule before you start. Don’t allow setbacks or blocks or anxiety to push you to say, “hey, maybe I should check my e-mail for a while, or you know, I could use a nap.” If you do that, the lizard brain will soon be trained to use that escape hatch again and again. "

― Seth Godin , Poke the Box