In Thinking, Fast and Slow, Daniel Kahneman references a fascinating experiment published in the Proceedings of the National Academy of Sciences that reveals a striking psychological and physiological insight: our decision-making is highly influenced by physical factors like hunger.
In the study, eight parole judges in Israel reviewed cases, spending an average of six minutes deliberating on each one. Across the day, only 35% of requests were approved on average. However, this percentage wasn’t constant—it varied dramatically depending on the time since the judge’s last meal:
- After eating, approval rates skyrocketed to 65%.
- As time passed, the approval rate steadily dropped to 0%, right before their next mealtime.
This illustrates the concept of “decision fatigue,” where the mental energy required for decision-making gets depleted over time. As their energy waned, the judges increasingly defaulted to the easiest and safest decision—denial. Hunger compounded this effect, further eroding their capacity for careful deliberation.
Application to Sales Teams
The lesson here isn’t to cut working hours to one hour after breakfast (though it might seem tempting for a laugh). Instead, it underscores the importance of aligning critical decision-making tasks or high-stakes interactions with periods of peak energy and focus.
Implications for Sales Teams and Productivity:
- Schedule important meetings or calls when energy is highest. Research shows that most people perform best within a few hours after waking up, making morning an ideal time for critical tasks.
- Incorporate regular breaks. Decision fatigue can build rapidly in sales, where every pitch, negotiation, and objection requires mental effort. Breaks help reset the mind and improve judgment.
- Provide nutritious snacks. Hunger clearly impacts focus and decision-making. Keeping the team fueled with healthy options like nuts, fruits, or protein bars can make a significant difference.
- Automate repetitive tasks. Automating low-value or repetitive activities reduces the mental load and preserves energy for high-value interactions.
- Monitor team performance patterns. By tracking productivity metrics at different times of the day, you can identify when your team is most effective and structure schedules accordingly.
The Science of Strategic Timing
This experiment teaches a profound truth: we are not as rational as we think, and external factors can have a disproportionate influence on outcomes. Applying this insight to sales—or any decision-driven environment—requires acknowledging human limitations and optimizing around them. By aligning effort with energy peaks and managing decision fatigue, you can significantly boost results and maintain a sustainable, high-performing team.