NoviceDesirability testing is mentioned as having taken place, but it’s not clear what the findings were, or how those findings translated into improvements to the design.
CompetentDesirability testing has resulted in some clear findings, which are addressed in iterations to the design.
ProficientDesirability testing has been done on the product itself, as well as with potential competitors or comparable products, to paint a more complete picture of how users would perceive the product. The connection between testing findings and design decisions have been made obvious.
ExpertDesirability testing has been thorough and yielded deep insights into user perceptions, resulting in clear improvements throughout the product. The product itself leaves no doubts about its desirability, as even small details have been considered.