What's the difference between model lines and kaizen events?
Dear Gemba Coach
We used to do six sigma and are new to lean. Some consultants talk to us about model lines and others about kaizen events. Can you clarify the difference?
That’s a difficult question, and I’m not sure I have all the answers. The various formats for “doing” lean emerged from the work Toyota was doing with its suppliers in the eighties, and the way that consultants interpreted it to sell projects to customers. What we’ve learned since is that the challenge is to become lean, rather than to implement lean, and so the various consulting formats don’t necessarily apply to every business. Let me recount what my father and I have learned from his experience of becoming lean under Toyota’s guidance back in the 1990s.
At the time, Toyota was toying with the idea of developing suppliers in Europe as they’d done in Japan. The situation was rather different. In Japan, many of their suppliers were part of the keiretsu. Many of the supplier’s managers were ex-Toyota employees, and Toyota was a dominant customer of most of their target suppliers. Not surprisingly, the suppliers were, if not eager, at least open, to learn more about TPS and the Toyota Way. In Europe, Toyota was starting its first European plant in the UK, had no pre-established relationships with supplier’s management, and usually represented a very small volume in any one supplier’s plant.
My dad turned out to be a natural candidate because as a Renault top executive he’d previously developed a long-standing relationship with Toyota TPS experts, and now that he was Industrial VP of a supplier, it made sense to start with him and a few others. As far as I remember, Toyota did start with a model line. They focused on one part, the light indicator, in one factory and invested quite a bit of resource in turning this production line into a lean showcase: one or two Toyota engineers visited the line on a monthly, sometimes weekly basis to spur kaizen. From my notes at the time the big fights were fought over quality and flexibility. The aim of the Toyota engineers was to turn the usual long-changeover, long-run, production line into a flexible cell which would produce five containers of five parts and then change reference. This had many technical and ergonomic implications as it meant modifying the machinery so that the lady operators on the line were able to easily (because of the number of changes) make the change. When the work started, tool changes needed a specialized setter who could not be available for such a frequency of changes. More frequent changeovers also created more frequent quality problems, usually at the setting stage which needed to be resolved.
Over the course of two years, the line evolved into a real “model” for all the TPS main principles: single-piece-flow, small batches, standardized work, andon, etc. As corporate level VP, my father visited the line regularly with a very senior Toyota guy who had learned TPS working directly with Taiichi Ohno. The line made considerable improvements, and it was then assumed by my father and his CEO that the trick now lay in “deploying” what had happened on the model line. So they sought to devise a cookie-cutter methodology they could then apply across all the 70 plus plants of the group. The idea was that a 5-day “kaizen event” would be sufficient to introduce the key principles of lean to any new cell and then local management could pick it up from there. The logistics of it seemed daunting, but hey, we’re talking about automotive and these guys don’t scare easy. Did it work? Well, something happened, but it’s hard to evaluate what with hindsight because of a huge wrong assumption.
The question Freddy and I asked ourselves much later was: what was Toyota after? They never asked for any compensation for all the time and effort during the project. Sure, they secured supplies at their standards from that line (in plain English, they colonized the line), but at a huge expense. Did they really intend the “model” line to serve as a replicable model that could be copied-and-pasted across the supplier? We don’t think so. Having talked it over for hours on end, we’ve come to see two large benefits to Toyota’s involvement:
- 30% total cost reduction (shared half and half) on the new product: sure there were productivity gains during the kaizen effort on the existing line, but nothing like the engineering impact of the learning from the kaizen on the next generation product. That was massive, and Toyota got out of it a 15% price reduction on the new product, with a supplier happy about it since they increased their margins as well: classic lean win-win.
- My father’s education: with hindsight, we also believe that Toyota was not trying to develop the supplier as a company, but to educate my father, who, as a senior executive would then have a disproportionate impact on the company. The “model line” on which the local engineers sweated so many tears was only a support device to get my father to learn first-hand the lean principles. And, as it turned out, the plant’s plant manager refused to get interested, and the plant never became lean, but the company as a whole did.
The model line, in this sense, was not about creating a “model” that could be replicated everywhere else (which we really believed at the time), but a laboratory to show my father how far they could take lean concepts, and with what impact both on the product and the process. To be fair, the deployment efforts did pay back because of the sheer gap of process knowledge, but the company never acquired the kaizen spirit underlying the TPS. It progressed, but then when my father left the company to become CEO of another automotive supplier, all progress stopped.
By that time Freddy had a well-established relationship with his sensei, and they no longer did a single model line. They visited various plants, and each time the sensei highlighted one specific issue. My father’s job was then to figure out a kaizen event with the plant manager to address this issue. It wasn’t that hard because most typical kaizen tools were well-known by then: 5S for visual management, flow-and-layout for productivity, SMED for flexibility, QRQC for quality issues, TPM for OEE, and so forth. But, yet again we missed the point—we were still obsessed with deployment, despite the fact that my dad had moved on from a tool-based program to a roadmap-based program. He was still trying to “deploy” lean. Again, with hindsight, we now see that the sensei was highlighting specific issues and was expecting specific responses from the plant’s management, in order for them to learn, and again, educate the CEO.
Lean Practice Basics
Rightly or wrongly I now believe that lean is about learning, whereas Taylor-ism is about deploying. six sigma projects involve a team of “experts” who will DMAIC a situation, come up with a solution and get the natives on the floor to execute. Lean, on the contrary is about learning-by-doing: specific events, whether model lines or kaizen events are designed to get local employees to learnt o solve issues and to educate senior management. The basic lean practice, I have learned is:
- Visualize activities
- Formulate problems
- Seek root cause
- Study countermeasures
The emphasis is on studying countermeasures: catch people doing something right, and more importantly, something they’ve not done before, check it, and learn.
To answer more directly, in this perspective, model lines serve as learning labs to see how far you can take an activity by applying all principles of lean in one area, whereas kaizen events are about tackling one typical issue repeatedly across various situations until one gets the hang of the typical solution, and a deep-felt intuition of the underlying principle.
Both model lines also illustrate a deeper aspect of lean, the spirit of challenge, facing one’s problems with creativity and courage. What we’ve learned is that rather than seeing both exercises as the consultant’s way to apply lean to whatever hapless team they’ve got their hands on, model lines and kaizen events are about striving to be better. Lean is not about pushing people to apply a process – it’s about giving them a faraway star to shoot for, getting them to build an ideal, and then see the gap with what we have and stretch themselves to figure out how to get there.
In other words, lean is about developing leaders, not followers. To develop followers, you will formulate a set methodology and get people to apply it, regardless of impact, by doing the P (Plan) and D (Do) of the PDCA. But to develop leaders, you get them first to do a kaizen to seek that frontier, that place where we perform better and then conduct a full PDCA cycle with check and act. To develop leaders, one shows them how far they can throw their javelin, and then ask them to figure out how to throw it that far every day, every hour, with every person. So both model lines and kaizen events are about making a special effort to see how good we can be if we try, so that we then figure out how to be this good every day, and then go further. Continuously.