This study presents a systematic literature review of the conceptual, methodological, and managerial toolset used to study and improve customer retention in digital commerce environments. Using a PRISMA-guided review of 44 engineering-oriented studies published between 2016 and 2026, the review synthesises how retention is defined, theorised, and empirically analysed across e-commerce, mobile commerce, social commerce, digital commerce, and on-demand service platforms. The findings indicate that retention is predominantly operationalised as loyalty, repurchase intention, or continuance intention and is primarily explained using technology acceptance and service quality frameworks. Methodologically, the field is dominated by cross-sectional survey designs analysed using Structural Equation Modelling, with limited use of behavioural or operational datasets. From an engineering perspective, the review demonstrates that customer retention is not a uniform construct but a system-level outcome contingent upon commerce architecture, trust locus, and dominant risk exposure. Retention mechanisms differ structurally across B2C platforms, social commerce, resource-constrained digital commerce, and on-demand service ecosystems. The study highlights the need for architecture-specific, analytics-driven, and intervention-oriented approaches that move beyond perception-based modelling toward optimisable retention systems.

Keywords

Customer retention; e-commerce; digital commerce; systematic literature review; framework; engineering design.