" executive and nonexecutive, every day. Yet few people are even aware of it. When asked whether making decisions would deplete their willpower and make them vulnerable to temptation, most people say no. They don’t realize that decision fatigue helps explain why ordinarily sensible people get angry at their colleagues and families, splurge on clothes, buy junk food at the supermarket, and can’t resist the car dealer’s offer to rustproof their new sedan. "

― Roy F. Baumeister , Willpower: Rediscovering the Greatest Human Strength