The Monday Blues

With the impact of COVID-19, Americans across the country went from wishing for the weekend, to living it daily. To many, it is feeling a bit like the film Groundhog Day. But the current state of the country won’t last forever, and before too long Americans will be back to counting down for the weekend. The typical countdown begins when they arrive to work on Monday. From there, it’s “hump day” on Wednesday and it continues until Friday finally arrives.

New research in the INFORMS journal Information Systems Research shows there are some undesirable lasting effects from the weekend into the start of the work week. The “Monday Blues” cause negative ripple effects on supply chains because of humans. But it’s not all bad news; for computers and machines, Monday is just another day.

My co-authors — Martin Dresner of the University of Maryland, College Park, and Kevin Zhu of the University of California, San Diego — and I found that the letdown of returning to work after a weekend causes interruption that hurts supply chain performance. That means a longer time between when a purchase order is received and when it is shipped, as well as more errors in order fulfillment.

To put it simply, the “Monday Effect” is real and it’s impacting package delivery.

My colleagues and I used a dataset of more than 800,000 transaction records gathered during a 12-month period from the U.S. General Services Administration to look at changes in operational performance by days of the week. We also analyzed order and fulfillment data from one of the largest supermarket chains in China.

We found time between receipt of a purchase order and shipping is more than 9 percent longer on Mondays than other days of the week. The findings show weekends create bottlenecks at distribution centers that are tackled on Mondays as orders are processed, picked, staged and shipped to customers. Humans completing these processing activities are negatively impacting these supply chains because they are readjusting to returning to work on Mondays and are less efficient and more prone to errors.

Supply chain managers can take steps to counteract this problem by increasing staffing on Mondays — or any day returning from a break, including holidays. Also, changes to schedules that include decreasing the number of Monday meetings and nonfulfillment activities can have a positive impact. Management can also put resources toward better training, additional pay, and/or mood-lifters such as free coffee or motivational talks.

But the most effective way to reduce the Monday performance gap is integrating technology solutions. One way to do this is to introduce automated order processing systems. The research shows that using electronic markets can improve Monday performance by as much as 90 percent.

Technology is proven to reduce the Monday performance gap by 94 percent in order-to-shipping time, 71 percent in complete orders fulfilled, and 80 percent in the portion of shipments that have incorrect numbers of products.

Technology was most useful in orders of specialized, less frequently purchased or high-value products, about which employees might be less knowledgeable.

When humans are more prone to make mistakes, technology has proven to be helpful in substituting labor. So, instead of businesses feeling the heat of the “Monday Blues,” they can now educate themselves on appropriate solutions and use computer-to-computer links to avoid potentially negative human effects resulting from the weekend break.

Oliver Yao is a professor of decision and technology analytics in Lehigh University’s College of Business. He is also a member of the Institute for Operations Research and the Management Sciences (INFORMS), the largest international association of operations research and analytics professionals.