The Goal

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a red" tag. Somewhere behind it all, its own hugeness obscur ed from our view, is the NCX-10.

"How do we get there from here?" asks Ralph, looking for a path through the inventory.

"Here, let me show you," says Bob.

And he leads us through the maze of materials until we reach the machine.

Gazing at all the work-in-process around us, Jonah says to us, "You know, I would guess, just from looking at it, that you have at least a month or more of work lined-up here for this machine. And I bet if we went to heat-treat we would find the same situation. Tell me, do you know why you have such a huge pile of inventory here?"

"Because everyone ahead of this machine is giving first pri- ority to red parts," I suggest.

"Yes, that's part of the reason," says Jonah. "But why is so much inventory coming through the plant to get stuck here?"

Nobody answers.

"Okay, I see I'm going to have to explain some of the basic relationships between bottlenecks and non-bottlenecks," says Jo- nah. Then he looks at me and says, "By the way, do you remem- ber when I told you that a plant in which everyone is working all the time is very in efficient? Now you'll see exactly what I was talking about."

Jonah walks over to the nearby Q.C. station and takes a piece of chalk the inspectors use to mark defects on the parts they reject. He kneels down to the concrete floor and points to the NCX-10.

"Here is your bottleneck," he says, "the X-what-ever-it-is ma- chine. We'll simply call it 'X.' "

He writes an X on the floor. Then he gestures to the other machines back down the aisle.

"And feeding parts to X are various non-bottleneck ma- chines and workers," he says. "Because we designated the bottle- neck as X, we'll refer to these non-bottlenecks as 'Y' resources. Now, for the sake of simplicity, let's just consider one non-bottle- neck in combination with one bottleneck..."

With the chalk, he writes on the floor: