Once we know something, it becomes hard to imagine what it feels like not to know it.
More quotesA field study offered hand lotion with either a 35 per cent price discount or 50 per cent more product. The larger percentage attracted more purchases even though the offers were economically equivalent.
The comparison is easy to misread because each percentage uses a different base. The number 50 looks larger than 35 before the shopper has converted both offers into price per unit. Similar presentations appear when a small original quantity doubles, a modest battery life receives a large relative improvement, or a bonus pack increases the amount bought as well as the amount received. Extra volume may be useful. It may also expire, require storage or cost more today. The visible percentage alone says little about those consequences.
Good price presentation includes the old quantity, new quantity, total price and a comparable unit price. The promotional percentage can attract attention while the denominator remains visible enough to support the claim. In the shop, few people want to calculate two changing bases beside the shelf. They see 50 before 35 and make a decision under time pressure. The unit price is printed on the shelf edge in smaller type, and the trolley moves on. Most shoppers do not turn back to check it.