"The Machine That Changed the World" is a wonderful title on this. Kiichiro Toyoda invented the lean production model after coming to the states and studying the inefficiencies of the assembly lines of Ford. This was a process dependent on modularizing every manufacturing component due to a demand for the Toyota company to serve a market with a need for an immense variety of vehicles, and giving teams ownership of the entire production process rather than one error check at the end a lá Ford. Introducing a vehicle with a steering wheel on the opposite side might take a year to implement in lean production, while handling that kind of variation in the assembly line model could take years (generally double the amount of time); The net result of this being that Toyota could offer 2x the vehicles of GM at half GM's size. Toyota was able to make extremely reliable vehicles and modify them as consumer demands shifted. By 1990, the Japanese were making cars with 4 year product lives and 500k total units (125k per year) while the Western companies were building 2M over 10 year product lives.