Elaborating Theory of Swift Even Flow in E-Fulfillment Operations

Abstract

Retailers struggle with late deliveries, thus motivating research to improve e-fulfillment performance. Studies have primarily investigated order processing and delivery individually but have ignored the interplay between these two e-fulfillment activities. The Theory of Swift and Even Flow (TSEF) provides a useful frame for examining the e-fulfillment process, yet it neglects important behavioral factors. We elaborate the TSEF using logic from the Queue-Length Visibility and Misperception of Feedback Dynamics perspectives to unveil how behaviors in order processing and delivery contribute to delivery performance. We analyze 11,241 orders from a major Vietnamese retailer using econometric methods informed by practitioner interviews. We find a concave relationship between order processing time (OPT) ratio (defined as the proportion of planned lead time consumed by order processing) and lateness. Late orders have OPT ratios exceeding 25% of the planned lead time, and they exhibit higher OPT variance. We also find a U-shaped relationship between OPT ratio and order delivery time (ODT); expediting deliveries mitigates delays until OPT ratios reach a threshold of 58%. Finally, we argue that workers and managers prioritize the processing of focused orders. Understanding behaviors in the e-fulfillment process offers insights that extend the TSEF, new research areas, and managerial implications.