Manufacturing productivity: Work less, accomplish more

A review copy of Jim Womack’s Gemba Walks, published by the Lean Enterprise Institute, came in the mail today, and I’m beginning to make my way through it. When I saw the title, I immediately thought of a scene in The Goal, Eliyahu Goldratt’s business novel on the theory of constraints. In it the plant manager walks the floor and spots a few workers sitting by the loading dock, doing nothing--on the clock. Once the workers see their boss, they immediately return to their workstations and start churning out parts.

By the middle of the book we learn just how wasteful churning out parts really is. The plant has piles of parts and a warehouse chockfull of finished goods. Some finished products sit so long that they become obsolete before the company has a chance to sell them.

So what’s more wasteful: idle, on-the-clock workers, or those idle parts in the warehouse?



Job shops build to order, not to forecast. Still, how serious a problem is an idle worker? Judging by the various job shops I’ve covered, idle workers really aren’t the problem; it’s idle parts, including excess work-in-process (WIP). If parts are moving, WIP is minimal, and the plant is running close to “on edge”--that is, with minimal WIP buffers--lead-times probably are pretty competitive. If a job shop can churn out a job days or weeks faster than the competition, idle workers may not be a problem.

Instead, keeping an eye on part movement may help identify waste and subsequent opportunities for improvement. Say a pile of parts sits in front of a robotic welding cell, where a technician is setting up as fast as he can. WIP grows as laser cutting, punching, and press brake operators feed parts to the joining area. Not all operators may be busy, though. Some people in the press brake department, for instance, may have nothing to do.

That excess WIP is trouble, and those idle workers may be a symptom. It means the floor isn’t producing as much work as it could. In this case, cross-trained operators may help. In one shop I saw a press brake operator move over to a robotic welding cell to help welding personnel relieve the bottleneck.

As workers operate more efficiently, they accomplish more in less time, which may give them time to cross-train in other processes. Cross-training can be vital in job shops. I’ve talked with some shop owners who base wages in part on a worker’s training on multiple processes. The more processes an employee knows, the bigger his paycheck.

An idle worker in such an environment probably isn’t lazy. If he has nothing of value to do--such as cross-training, inspection, or relieving bottlenecks elsewhere in the plant--why should he be working? In fact, idle time may even be a very positive thing. If a company has short lead-times, strong cash flow, and healthy profits, it means workers are accomplishing more in less time. And they may be getting paid the same wage or, because of the company’s financial health, even a little more.

The last time I checked, people don’t mind getting paid more for working less.