Investigating the Influence of Queuing Theory Parameters on Customer Satisfaction at ZANACO: The Mediating Role of Customer Waiting Time

This study examines the influence of queuing theory parameters on customer satisfaction through the mediating role of customer waiting time at Zanaco Cairo Road Branch in Lusaka, Zambia. In retail banking, service efficiency remains a critical determinant of customer satisfaction; however, prolonged waiting time persists as a significant operational challenge, particularly in high-traffic branch environments within developing economies. Despite advancements in digital banking and queue management systems, congestion in physical banking halls continues to undermine service experience. This study addresses this gap by integrating queuing theory with expectation–disconfirmation theory to explain how operational system characteristics influence customer satisfaction outcomes. Anchored in a critical realist philosophy, the study adopts a sequential explanatory mixed-methods design. Quantitative data were collected through structured observations and customer questionnaires, while qualitative insights were derived from semi-structured staff interviews. Findings indicate that customer arrivals are highly concentrated during peak hours, resulting in demand–capacity imbalances and system congestion. The average waiting time significantly exceeds accepted service benchmarks. Regression analysis shows that queuing theory parameters significantly predict waiting time, while waiting time has a strong negative effect on customer satisfaction, confirming its mediating role. Qualitative findings reveal that staffing constraints, transaction complexity, and system inefficiencies are key drivers of delays. The study concludes that customer waiting time is the critical mechanism linking queuing system design to customer satisfaction. It recommends dynamic capacity alignment and process optimization to enhance service efficiency and improve customer experience in retail banking.