The first was to concentrate mainly on the product and assume that everything important about it was somehow implicit in its attributes, without regard to what role the customers wanted it to play—the job they were hiring the milkshake for.
The second mistake was to adopt a narrow view of the type of food people have always eaten in the morning, as if all habits were deeply rooted traditions instead of accumulated accidents. Neither the shake itself nor the history of breakfast mattered as much as customers needing food to do a nontraditional job—serve as sustenance and amusement for their morning commute—for which they hired the milkshake.
aggregate this available but dispersed knowledge, to collectively weave together all the piecemeal awareness among individual witnesses into a nationwide picture.
You don’t need fancy computers to harness cognitive surplus; simple phones are enough.