Lean

In the TPS Principles and Practice discussion group on LinkedIn, Emmanuel Jallas asked whether visual management was a “lever to make other tools work, or  a tool by itself.”

• Visual management as embedded into other tools
• Visual management and Potemkin villages
• Visual versus verbal communication
• Visual management as part of the information system
• Japanese terms for visible management

Visual management as embedded into other tools

As I see it, visual management should be part of everything else we do, but not treated as a stand-alone topic. Visual management should be considered in the design of a plant, a production line, a supermarket, a shipping/receiving area, a crossdock, a cafeteria, a restroom, etc. It is part of setup time reduction, cell design, or kanban implementation. It make visual management a “tier 2” tool.

If, however, you try to discuss it or teach it as a stand-alone, generic subject, you quickly get dragged into what it involves in different, specific contexts. If you have a mixed group, whatever you say will only be of interest to a minority at a time. On the other hand, if you are teaching Lean Logistics, then the discussion of visual management in materials handling comes naturally.

If you write a “How to” guide, you really have to think who your intended readers are. If you write on how to design a machining cell, you know exactly who they are. And, if you do a good job of writing it, all of it will be of use to this audience.

But who is the audience for visual management? It’s everybody! But the general theory of visual management fits in a few pages. After that, you have to go to examples, and each example is for an application that is only of interest to a tiny sliver of a manufacturing organization. So maybe 1% of your How-to book is of interest to each reader, but you can’t cut any of it, because another reader’s 1% is somewhere in the  remaining 99%.

By the way, people like Gwendolyn Galsworth or Michel Greif, who have written several books on visual management obviously disagree with me on this. I use their books like dictionaries, not how-to guides.

Visual management and Potemkin villages

Since visual management is, … visible, it is commonly part of the Potemkin villages put up by companies that want to look lean to outsiders. But the fakery is easy to spot when, for example, you see bins under a sign that says the area should be clear, the operators don’t know what the colors on the andon lights mean, the color codes are inconsistent across the floor, or a production monitor shows overproduction and production continues,… It does not take many discrepancies to torpedo the credibility of visual management.

Complicated color codes are a tell-tale sign that a system is not used.  The andon lights I have seen in Japan have only three colors with one and only one solidly lit at a time. It’s Red, Yellow, and Green, with Red meaning that the machine is stopped, Yellow that it is available, and Green that it is working. Used consistently throughout a shop floor, it gives you an overall equipment status at a glance.

Of course, the light suppliers prefer to sell more elaborate models, but I have never met an operator who could tell me what White with blinking Blue was supposed to mean, especially when it was not consistent across machines. So, if you see that, you know that the lights are just there for decoration.

Visual versus verbal communication

Reliance on words is not recommended for an audience that does not have a common language. That is why traffic signs in Europe are mostly wordless and European car dashboards are covered with pictograms, that are sometimes but not always self-explanatory, which is why I have taken to calling them “euroglyphs.”

An American car dashboard with words is actually easier to understand, but only if you know English. Like European roads, a California production shop floor may have a work force with multiple nationalities and uneven English proficiency. As a consequence, using words for instructions or safety warnings is not much of an option.

Two resources I find helpful is thinking through these issues are usability engineering experts Don Norman, author of The Design of Everyday Things, and Asaf Degani, author of Taming Hal.

If you include hearing, touch and smell, I suppose it should be called “sensory management” rather than “visual management.” If we use “visual management” for all forms of sensory management, what term are we going to use for what is specifically visual?

Visual management as part of the information system

The term “information system” should encompass all the means used in a plant to exchange and process information. Visible management is part of it, along all the computer applications, from CNCs, PLCs and SCADA systems to corporate servers for technical and business data. They are all components of the same information system and both are needed to run a plant.

Japanese terms for visible management

The Japanese term I have heard for visual management is ”medemirukanri”(目で見る管理), literally “management you can see with your eyes.” Mieruka (見える化) is new to me; it means “transformation into something visible.” I see it as an improvement, as it is shorter and just as self-explanatory. I suppose you could say that medemirukanri is the result you achieve and mieruka the process by which you achieve it, but I don’t see that nuance in the usage.