People get out of balance when they see their value as being able to respond quickly. If I see myself as a machine for answering email, then my work life would never stop because my email never stops. If instead I see my value as separating the important from the unimportant and making good decisions on the important, then I can go home at a reasonable hour, spend time with my family, ignore my email and phone messages all weekend long, and make sure that when I return to work, I am in the right mood to make the good decisions.
by Peter Norvig - dyrektor ds. badań w Google'u