Recognizing that companies went bust when the market for their products dried up, Levitt set out to learn why. The manifesto he produced aimed to upend conventional wisdom that viewed a company's product as paramount. Levitt saw the customer as central to the success of any business, and urged companies in every industry to look at their products from the customers' point of view. His ground-breaking 1960 article established him as "the father of modern marketing." At the time, marketing did not even exist as a separate business discipline. But straightforward writing style and real-world case studies helped make Levitt's paper part of the core curriculum at business schools.