Ever feel mentally drained after a long day of choices — from what to eat for breakfast to which email to answer first? That’s decision fatigue at work. Discover what it is, why it happens, and science-backed strategies to reclaim your mental energy. Key Takeaway The average adult makes approximately 35,000 decisions per day. Each one draws on a finite pool of mental energy. When that energy runs low, the quality of your decisions drops — often without you realizing it. What Is Decision Fatigue? Decision fatigue is the deteriorating quality of decisions made after a long session of decision-making. Unlike physical fatigue, which is obvious and measurable, decision fatigue is subtle — it creeps up on you, disguised as irritability, impulsivity, or a sudden inability to make even simple choices. The term was popularized by social psychologist Roy Baumeister, whose research on " ego depletion " showed that willpower and decision-making rely on th...