ABSTRACT
The ultimate test of a Stage 4 plant is when you can take your spouse or a friend who is unfamiliar with the operation through your plant and they can figure out what is going on with little explanation. It should be that obvious and simple. One of the best visually managed plants I ever saw was a Yazaki assembly plant near Monterrey, Mexico, in the mid-1990s. When I walked into the plant, the first thing I noticed is that nothing in the entire plant was more than chest high-even the employee lockers. You could literally see the entire plant from the entrance, and it was spotless.
