Kaizen is a Japanese word meaning improvement, and outside Japan it describes a business approach built on continuous, often small changes. The idea is that many modest improvements to every part of a company's operations can add up to significant results. Everyone takes part, from the chief executive to assembly-line workers, and it extends to suppliers and logistics across the whole supply chain. Its goal is to eliminate waste and redundancy, using existing resources rather than large investments, which is why it is sometimes called zero investment improvement. The concept grew out of work by American advisers helping rebuild Japan after the Second World War. It was adopted by Japanese firms and became part of the Toyota Way, and it has since spread to healthcare, education and other fields.

In 1909 D. W. Griffith made a 14-minute film about a speculator who corners the wheat market and doubles the price of bread. A farmer sows his field while a 'Wheat King' gambles in the Chicago wheat pit; bakers raise the loaf from five cents to ten and the poor line up for bread. Griffith cut back and forth between the farm, the feast and the breadline, a technique called parallel editing, so audiences saw both ends of the economy at once. The film drew on Frank Norris's stories and on a real scheme: months earlier Chicago financier James Patten had cornered wheat, sent bread prices up and made about $5 million, roughly $185 million today.