The History of Lean

Traditional manufacturing is based on the ability to efficiently produce high quantities of products. Mass production, as that is known, first became possible back in the 1800s, when the Springfield Armory in Massachusetts began using interchangeable parts and standardized production methods.

However, mass production created a new set of issues, namely large inventories and a high potential for obsolescence, as products sat around for months and years without being sold – problems that manufacturers still struggle with today.

Another milestone occurred when Henry Ford developed the modern assembly line and began churning out Model T’s by the millions, making the automobile an affordable reality for the first time. However, there was no production flexibility – each of the early Model T’s was exactly the same. As the joke went: "You can have it in any color… as long as it’s black."

Fast forward to the 1950s and Taiichi Ohno, who worked for a small and nearly bankrupt Japanese automobile manufacturer, named Toyota. At the time, Toyota was under enormous pressure to cut costs and increase efficiency. Ohno went to the United States to study Ford’s assembly lines. He returned to Japan and, with his colleagues at Toyota, developed the Toyota Production System, widely considered the finest manufacturing model in the world – and the foundation of lean manufacturing.

At the time Ohno and his team were developing Toyota’s new production system, the company didn’t sell enough of a single model to justify Ford’s mass production techniques. Plus they couldn’t afford the complex machinery thought to be the key to increasing productivity.

So they focused on relentlessly eliminating wasted time and activity in every part of the manufacturing process. As a result, they were able to dramatically cut costs and production lead times. They also developed a breakthrough process for rapidly changing over equipment and production lines to produce different models. As a result, Toyota was able to make a variety of models on the same production line.

To help explain the Toyota Production System to employees and suppliers, the “House of Toyota” graphic was created by Taiichi Ohno and Eiji Toyoda. They chose the house shape because it was a familiar one – and also conveyed stability. The roof contains the primary goals of TPS: superior quality, cost and delivery through waste elimination.

The Toyota Production System has enabled Toyota to consistently produce vehicles far faster and more efficiently than their competitors, a critical advantage. Toyota passed Ford in 2004 to take the number two position in worldwide vehicle sales – and claimed the number one position from long-time leader General Motors in 2007.

Now for the Six Sigma component of LeanSigma. More…