Recent research from the Wharton School at the University of Pennsylvania reveals that minor workplace slights can significantly impact employee productivity. The study, published on January 16, 2026, highlights how seemingly trivial oversights, such as forgetting to wish employees a happy birthday, can lead to a dramatic increase in absenteeism and reduced working hours.
Researchers observed that when managers at a national retail chain failed to deliver birthday greetings on time, absenteeism surged by 50%, and employees reduced their working hours by more than two hours each month. This lost productivity was described as a form of retaliation; employees took more paid sick leave, arrived late, and extended their breaks.
Understanding the Impact of Minor Oversights
Professor Peter Cappelli, along with colleagues Liat Eldor and Michal Hodor, aimed to examine the minimum threshold of mistreatment that would lead to workplace problems. Their findings challenge the notion that only severe mistreatment affects morale and productivity. The study is the first to quantify the effects of minor infractions on employee behavior.
The team selected a retail chain with a policy requiring managers to personally deliver birthday cards and small gifts to employees. This approach was intended to foster personal connections and strengthen the relationship between employees and managers. Detailed records of employee performance, along with adherence to the policy, provided an ideal environment for the research.
The results showed that when birthday greetings were delivered within a five-day window of the employee’s birthday, there were no adverse effects on productivity. However, delays beyond that window resulted in measurable declines in performance. Absenteeism returned to normal levels once employees received their gifts.
A Lesson in Perspective
Cappelli noted that the findings serve as a reminder for managers regarding the significance of interpersonal skills in the workplace. While managers interviewed for the study did not intend to overlook these small gestures, their focus on operational demands often led to these oversights. The results suggest a disconnect between managers’ intentions and employees’ feelings.
“It’s a different perspective on the same phenomenon,” Cappelli explained. Even minor delays in recognizing personal milestones can leave employees feeling undervalued. He emphasized the importance of acknowledging significant events in employees’ lives, such as birthdays, graduations, and personal losses, to enhance their sense of worth in the workplace.
The study also points out that while managers play a role in employee mistreatment, it is vital for organizations to foster an environment that values personal relationships. Simple acts of recognition, such as delivering a birthday card on time, contribute to a culture of respect and appreciation. Cappelli concluded, “Manners matter. Giving somebody a birthday card and getting it to them on time is good manners.”
The research was published in the journal Proceedings of the National Academy of Sciences, underscoring the significance of addressing even the smallest slights to maintain a productive and engaged workforce.
