Modern retail stores that offer a large section of similar products, especially in a complex or infrequently purchased category, create a difficult task for the shopper. Many of those purchase decisions are automated.
To pick the best alternative, or at least find what they are looking for, shoppers must closely examine the different products by reading the packaging text or consult a store staff member.
Some shoppers, unwilling to invest significant time and effort in their purchase decision, will simply pick whichever item is on promotion. Others will become frustrated and leave the store. When shoppers have limited motivation or ability to process information, stores should provide a small set of visually distinct alternatives where the visual differentiation reflects important differences in features and benefits.
Product assortment should be defined by the variety of consumer needs, not the number of SKUs. Branding and packaging should communicate real product differences, not hide the similarities between commodity products.