Mortgages, for example, made it easy for consumers to shop for ever-cheaper deals, pressing appraisers who increasingly relied on Internet tools to evaluate properties and loan prospects, instantly.
The theory of user-driven innovation comes from MIT professor Eric von Hippel, who proposed that when tools are placed directly in the hands of people who have the most pressing needs for answers, innovation happens, because there is no longer a need to transmit requirements from one person (or group) to another.