I recently went to a talk by an architect from Continuum and he described his experience working with Pampers.  Pampers became really successful because of their marketing and design. They brought in some mothers and babies to see what they wanted in a diaper.  They put a researcher out in the waiting room with the mothers and listened to their conversations.  They basically overheard the moms bragging about the development of their own kid (“My kid started to crawl”.. “My kid….”).  After this they realized that when buying diapers mothers didn’t care about the actually technology and how much liquid it can hold, they just care about the development of their own kid.  This is why they marketed their product as they did and put an elmo and big bird on the back of the product (which also reminds parents of development). Then the Pampers diaper (which is no different than any other brand of diapers), became so desirable.