Dual emotional mechanisms of fear of exclusion and fear of missing out: Extending the S–O–R framework in social commerce repurchase behavior

This study advances the theoretical understanding of emotional mechanisms in digital consumer behavior by integrating Fear of Exclusion (FOE) and Fear of Missing Out (FOMO) as dual emotions within the Stimulus–Organism–Response framework. Drawing on Self-Determination Theory and Social Comparison Theory, the research explores how personal and influencer traits, positive information, and social media usage intensity interact to shape these emotions and their subsequent effects on brand trust and online repurchase behavior. Using data from Vietnamese social commerce users across major platforms, the model was tested via Partial Least Squares Structural Equation Modeling. Results reveal that FOE significantly predicts FOMO and directly affects repurchase behavior, while FOMO enhances brand trust and indirectly drives repurchase intention through trust formation. Furthermore, FOE and social media usage act as moderators amplifying the behavioral effects of FOMO, supporting the dual-emotion interdependence hypothesis. The study extends traditional emotion-behavior frameworks by introducing dual emotional mechanisms, demonstrating that exclusion anxiety and opportunity-missing fears operate as interconnected affective states rather than isolated emotions. These findings enrich current perspectives on social commerce psychology, consumer trust formation, and the emotional foundations of digital loyalty, offering theoretical and practical insights for platform designers and brand strategists.