Onur Cobanli explains:
Good design sells. Great design sells better. A product’s design must appeal to consumers and perform well in the marketplace. Sales are a key indicator of how well an industrial design meets market needs and preferences. Remember, for industrial design; it must sell because its purpose of creation is to satisfy a demand, and if it does not sell (when the price is right because if price is high it will not sell good) then the work is not good design; it means it fails to create or satisfy demand.