What consumers want, and what you produce, aren’t always the same.

This lesson has been repeated many times over. In 1960, the editor of the Harvard Business Review, Theodore Levitt, wrote that the failure of railroads could be explained in part by the myopic view that they were in the railroad business and not the transportation business, which left them vulnerable to competition from cars, trucks, and planes. Levitt argued that it’s always better to define a business by what consumers want than by what a company can produce. Kodak had built a successful enterprise producing cameras, film, and photographic paper and chemicals, but what people wanted was images, and so when a better way to get those images was found, its customers followed.

http://blogs.hbr.org/cs/2012/09/what_is_the_business_of_health.html