By Kevin Meyer
A couple weeks ago I re-read Michael Balle's excellent business novel, The Lean Manager. One concept that has been nagging at me is the idea of flexibility as a form of waste. Most of us in the manufacturing environment work hard to cross train so that operators can flow between processes and stations, usually in an attempt to reduce batch size and improve general knowledge.
The lean guru in Michael's book looks at it from a different perspective, when mentoring his plant manager on how to create basic stability through stable part families that go through stable processes and dedicated equipment.
"Next you're going to tell me that the operators should always be at the same station, working on the same parts to gain as much familiarity as they can on the parts."
"And how is that surprising? Do you do any sports?"
"Me?" he laughed. "No, it is against my religion. But my wife trains competition jumpers. Why?"
"Does she? So here's a big puzzle. If one rider is trying to win a specific event, should he train every day on a different horse on a different type of course in order to learn riding 'in general' or would he —"
"Ride the same horse on the same course every day to know the animal's reactions and the terrain by heart. You're right, it's pretty obvious. But we can't keep operators at the same stations all the time."
"Why?"
"Well, any one station doesn't operate continuously."
"Why?"
"Because… ok, I get it. We're not producing at the customer's rhythm, so we're creating inventory while moving people around. It's dumb."
"The 'flexibility' you have in mind is not true flexibility. It's keeping for yourself the latitude of moving people around if one station is down, so you can maintain your efficiencies by working on something else while you take your sweet time fixing the equipment. And so what you get is 'flexibility' for your production manager, not for your product flows. In effect, it's a license to accept waste." [pages 92-93]
This idea startled me at first. It took a second read to realize he's not suggesting eliminating cross training, but instead having dedicated people and processes and equipment. The same operator, or operators, work on smaller and smaller batches at the takt of demand across smaller intervals of time, which may not fill a full day. In those cases a change is made to different products and even processes, requiring people trained in multiple operations, but the same people still work on the same parts.
Note the use of "Why?" and how the CEO in this case is teaching his plant manager by challenging the process and developing solutions… at the gemba. This lean leadership model is pervasive throughout the story, and a reason why I highly recommend the book.
Lester Sutherland says
Kevin,
I have a slightly different take on what Michael Balle was point out at this piece of the novel. Not that flexibility is bad or causes waste, but rather the way it was being used. Using flexibility to protect for machines breaking down takes the pressure off the factory to make sure they never break down, and that was the point being made (IMHO). Flexibility and Rotation are not always wasteful, because they can help with other issues which may be worse such as ergonomics and boredom. Of course that is after a person has trained on a job long enough to know the job, and is ready to rotate. It really depends on the situation, but a good experienced worker, and a good experienced horse trainer, rotates between machines and horses with no waste.
Mark Welch says
My take on this was a little different. I was thinking that although rotation (flexible, motivated workforce) is generally good, the fact that a process needs rotation at all might also imply line imbalance. In other words, the challenge went out to the student to balance the line better – to takt – so they wouldn’t HAVE to rotate. Difficult to achieve, I know, but goes hand in hand with the pursuit of perfection…
Jon Miller says
Flexibility is a word that is often misused in manufacturing. People think that being able to respond to and cover up any problem so that it does not affect the customer equals flexibility. This is more true the higher up you go in the organization, since the sale and the satisfied customer is everything. As a result “flexible” manufacturing is full of inventory, excess equipment, and people who are trained to react to problems.
The discipline of exposing problems and rapidly correcting them goes hand in hand with having a certain level of stock, excess equipment and cross trained people based on the uncontrollable level of variability in demand, or the customer service levels you must maintain based on current conditions.
From the point of view of developing people by providing them with more skills, I would never let the arguments above dissuade you from doing cross training.
Jim Fernandez says
This is very interesting. And I’m sure the way we all interpret this concept is based on our experiences.
When I read this; “And so what you get is ‘flexibility’ for your production manager, not for your product flows. In effect, it’s a license to accept waste.” I took this to mean that the process was so out of control that the work force became “flexible” in order to get the product out the door.
It reminded me of something that I heard when I first started working at my current place of employment: “Oh it’s always been like this. But we are smart and we work around these problems every day”.
And this is exactly the situation at my company. When I first started to map the value streams here where I work, it was a nightmare. As soon as I got a map done 80% of it was wrong. Because the workers had moved and the value stream (work area and equipment) was producing a different product. My company is a low volume high mix manufacturing plant. And believe me when I say for the most part our flexibility evolved specifically because of our waste. And it hides our waste. Our flexibility is our license to accept waste.
Bill Waddell says
I have seen the opposite far more often than I have seen examples such as the one cited. Numerous factories continue to produce because the operators only know how to do one thng – so they make that thing even when there is no demand. Far better to have flexible, trained people who can do a number of things – and can be moved from machine to machine as needed to react to variations in demand.
I wholeheartedly agree with Jon Miller when he said, “I would never let the arguments above dissuade you from doing cross training.”