Toyota did not have the luxury of creating waste, it lacked warehouse and factory space and money, and it didn't produce large volumes of just one type of vehicle. But it determined it could use Ford's original idea of continuous material flow (as illustrated by the assembly line) to develop a system of one-piece flow that flexibly changed according to customer demand and was efficient at the same time. Flexibility required marshaling the ingenuity of the workers to continually improve processes.