A new study from Tel Aviv University (TAU) and George Washington University finds that billions of dollars in lost e-commerce revenue may be driven less by cost or shipping concerns and more by how shoppers feel about what’s in their carts.

Shopping cart abandonment remains one of the biggest challenges in online retail. Industry estimates suggest that more than 70% of online shopping carts are abandoned before checkout. By the time a customer reaches this stage, retailers have already invested heavily in advertising, logistics, and website experience. When purchases aren’t completed, those investments fail to generate expected returns — adding up to billions in lost revenue each year.

Now, new research points to a powerful psychological factor behind this behavior: guilt.

The study was conducted by Professor Liat Hadar, Professor Yael Steinhart, and Professor Yaniv Shani from TAU’s Coller School of Management, together with Dr. Gil Appel of the George Washington University School of Business. It was published on February 4, 2026, in the Journal of Consumer Research.

The research reveals that shoppers are more likely to abandon their carts when those carts contain a higher proportion of “indulgent” items — products associated with pleasure rather than necessity. Indulgent items include products like sweets, scented candles, luxury personal care goods, decorative home items, or novelty products. In contrast, “practical” or utilitarian items, such as groceries, cleaning supplies, batteries, or basic clothing, are seen as necessary and functional.

Analyzing nearly 15 million online shopping instances, along with a series of controlled experiments, the researchers found a consistent pattern: the more indulgent a cart appears, the less likely a customer is to complete the purchase. This effect held true regardless of total price, number of items, or time spent browsing.

According to the researchers, the explanation lies in how consumers justify their spending. When a shopping cart feels overly indulgent or non-essential, shoppers may experience guilt or a sense of wastefulness. This internal conflict can lead to hesitation — and often results in abandoning the purchase altogether.

On the other hand, adding practical items to a cart can create a sense of balance. Even when indulgent products are included, the presence of everyday necessities helps shoppers feel their purchase is more justified, reducing guilt and increasing the likelihood of checkout.

The findings offer clear, actionable insights for online retailers. For example, suggesting useful or practical items, such as everyday essentials or complementary products, during the shopping process may help customers feel more comfortable completing their purchase. Interestingly, these recommendations can be effective even if shoppers don’t ultimately add the suggested items; simply shifting the perception of the cart can make a difference.

“Our findings show that shopping cart abandonment does not stem only from technical considerations such as price or shipping, but from a deeper psychological process of purchase justification and guilt,” said Professor Hadar. “When the shopping cart is perceived as too indulgent, consumers may struggle to justify the expense and choose not to buy. Small changes in how carts are structured or presented can reduce these feelings and have a meaningful economic impact.”

The study highlights an important shift in how businesses should think about online shopping behavior. Beyond optimizing prices and delivery options, understanding the emotional experience of shoppers may be key to reducing cart abandonment and improving overall sales.