"No matter what we are designing, building, or helping to build, we want our products (including software, hardware, consumer goods, and services) to be useful, appreciated, and profitable. We want to help create products quickly and cost effectively, but with the right set of features and good quality. We want these products to hit the market and instantly inspire demand, desire, and loyalty. We want people to use our products repeatedly and happily, encountering just the right functions at the right times and finding that the products grow with them as they develop expertise. We want our efforts to result in products that delight people, and to delight people we have to have some idea of who these people are and what they want."
"The Persona Lifecycle" , John Pruitt & Tamara Adlin