The navigational structure presented to users of most online shopping sites is not conducive to promoting effective exchange. Whereas customers tend to mentally chunk products related to goals they are trying to achieve, most online stores simply present products in categories and force the user to connect the related categories as they navigate through the site. Instead of online stores organizing themselves based on actual customer mental processes, they instead organize themselves based on fairly obvious and simplistic groupings of product categories. To the online shopper this creates a conflict between the actual and desired navigation structure, resulting in user frustration and, ultimately, lost sales for the retailer.
Most online retailers organize themselves in a fashion similar to physical stores.
One significant distinction is that in an online environment since physical proximity of products is irrelevant there is no true browsing which can exist. A customer who browses through a physical retail store moves from product category to category, perhaps seeing things that will motivate a purchase. In an online environment organized by product category, this notion of browsing becomes cumbersome for the user. Although there are many things physical stores do well in merchandising their products, there are many things that they cannot do for reasons of practicality. These mitigating reasons do not exist in an online environment.