The perspective of power law of practice and human capital model asserts that cognitive search costs, cognitive transaction costs, and cognitive switching costs are three lock-in mechanisms that a business-to-consumer (B2C) Web site holds to retain customers. Whether the ability of customer value or the lock-in mechanism is more dominant for retaining online shoppers has received recent attention, but remains unresolved in the literature. This study sheds light on perceived value and cognitive lock-in to develop a research model to predict consumer purchase intentions. Empirical results obtained from a survey of customers of a B2C Web site are used to examine the proposed model. Implications of cognitive lock-in and product cues for increasing purchase intentions are also discussed.