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  • Writer's picturehidet77

Net Work

“Net work”

Not a popular word.

It appears in Taiichi Ohno’s book “Toyota Production System.” This word appears in the figure in the chapter “The Significance of Understanding.” (If I translate the title of this chapter, it would be “Meaning of Recognition.”) In this pie chart, the word “Net work” appears.

Looking at the pie chart, most will understand that “Net work” = “Value-add work.” And in the original Japanese version, Ohno uses the word “Net work” frequently. He describes it as “Net Work which increases the add-value.” Whenever he uses the word in the text, it is translated as “Value-add work.” It is known that Ohno and Toyota use the word “Net work” frequently, and it is understood in Japan that this means “Value-add work.” But do these two words mean the same?

The word “Net work” suggests something interesting. “Net” means what remains after deduction. In this case, there is gross movement (time). We remove the Muda (waste) and Non-value-added work; the remaining is the “Net work.”

This logic suggests one thing: we don’t define the value-add work first. Why is it possible to determine the “value” when you can’t recognize the waste? Focus on recognition of Muda (Waste).

When I visited a plant, the plant manager said, “Everything, starting from when the material enters our plant to shipping, is value-adding work.” Of course, that was a horrible plant. The condition will be wrong when the manager can’t recognize the waste. Unfortunately, some versions of such wrong understanding exist elsewhere. “We are at full capacity.” “Investment is the only way to improve.” “We need to add more people.” Diseases where we don’t recognize the waste are everywhere.

I had a time when defining the value-added work first was a better approach. I was in a metal machining center. I thought it was easy to determine the “value-added work” there since it generates some noise or light when machining happens. Those times with some light and noise will be the “value-added work” of the machine cycle time. Then, my coach asked a “weird” question: “Isn’t the machine cycle time too long?” I did not have any answers to that question and left. A few months later, an engineer came back to the discussion. He felt the question of my coach was weird, too, so he investigated. He discovered that machine cycle time increased after the material supplier changed. The new supplier had lower-quality materials. Therefore, the engineers added more materials, and that required more processing. As the plant manager heard the conversation, he asked, “Are you saying that our production cost increased to save purchasing cost? If so, how much?” In the end, the company was losing more than saving. This created a discussion about what value-added work in machining is. I quietly discarded my “Value-added work” definition. The machine was cycling but may be overdoing to cover some issues from suppliers.

There is a saying in Japanese chefs. “Salt calls for more salts.” We modify this and say, “Muda (Waste) calls for more Muda.” The value-added work is hidden under the layers of waste. We have to get there one by one.

The word “Net” is strange in Japanese. It is “Shoumi 【正味】.”

【正】means correct.

【味】means taste.

So why does “correct taste” mean “net”?

It is said that the word “Shoumi” was used in the fishing industry. When shrimp and crabs were sold, they were sold without the shells and heads. This sales condition was called “Shoumi volume,” the weight without unnecessary things. The business world then started to use volume without the packages. Eventually, it meant “net.” The word “Net work” is not an invention of Ohno or Toyota. It was used before. But sometimes “Net work” means the amount of time without breaks.

Can we say that “Net work” = “Value-added work”? Isn’t the true value-added work hidden inside the net work? Although this question might be correct, it is also too theoretical. “Net work” depends on the capability to recognize waste and Kaizen. When you can’t get to the “Net work 100%” condition, which Ohno states as ideal, what is the point of developing the additional concept? But this question allows us to challenge what is inside “Net work” continuously. “Net work” is based on the current capability to recognize waste and Kaizen, while true value-added work requires further development.

By the way, shrimp and crabs are considered auspicious food in Japan. Shrimp is written as 海老, meaning sea and elderly person, which probably came from the shape. Because of that, shrimp represent a long life. Crabs are symbols of certain shrines. Those shrines see crabs as messengers from god. One thing that fascinated the Japanese was the molting of shrimps and crabs. The molting was seen as the reproduction of life. As a result, there is a Japanese idiom, “Break the shell.” This idiom means breaking the current thinking, habits, and methods and changing them to something new. When we “break the shell,” we reach the “Shoumi.”

I am not trying to change the translation between “Net work” and “Value-added work.” But I see the value of keeping the word “Net work.” When “Value-added work” floats by itself, some start to state that we must define the value first. Then, they start brainstorming about “value” in the meeting room and making beautiful presentations and Excel. And genba remains as is. As Ohno has stated, the key to all this is the capability to recognize waste and Kaizen. Without both, the “value” is “beautiful food drawn in the picture.”

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