“Heart it or cart it†: The mere placement effect and its impact on purchase likelihood

E-shopping often unfolds across multiple sessions, during which consumers frequently add products to carts or wishlists without deliberate intention to purchase. This research investigates the psychological consequences of such unintentional product placements and their influence on subsequent purchase decisions. Although common intuition suggests that cart placement reflects stronger purchase commitment than wishlist placement, our findings reveal a temporal shift in this pattern over time. Across two pilot studies and five experiments, we find that products placed unintentionally in wishlists are initially less likely to be purchased than those added to carts; however, as time elapses, the purchase likelihood of wishlist items increases, whereas for cart items it remains relatively stable. This counterintuitive pattern occurs because wishlist placement triggers purchase procrastination without decision closure, keeping the choice cognitively active. We introduce the mere placement effect, demonstrating a psychological mechanism through which incidental categorization into a cart versus a wishlist can influence subsequent purchase likelihood independent of initial intent. We further identify two boundary conditions: (1) temporal gap since placement, and (2) retailer communication type (price-promotion vs. reminder-messaging). These findings highlight the psychological role of wishlists, offer actionable implications for digital retail interface management, and suggest ways to support more intentional purchase decisions.