When the Endangered Species Act was signed in 1973, it was expected to protect charismatic fauna such as the bald eagle and Yellowstone's grizzly bears.
I found, as Hacker observed years before, that most wives want their husbands to be, first and foremost, conversational partners, but few husbands share this expectation of their wives.
Services are useful only insofar as they are consumed, and so the best way of specifying their usefulness is to describe what consumers expect of them.
Well before a championship, sports scientists and coaches start to prepare the athlete by developing a 'competition model', based on what they expect will be the winning times.