Recently, I had an opportunity to speak with someone who is working at Toyota. During our conversation, Taiichi Ohno’s name came up for the first time in quite a while. This person’s background was not in production engineering but in public relation. Yet when the conversation turned to a challenge on a manufacturing floor, he began to untangle the flow of the process and the points of stagnation with remarkable clarity.
That conversation brought something back to me: Taiichi Ohno’s classic book Toyota Production System. The first edition was published in 1978. When I was still in high school, a copy my father had finished reading was sitting in the living room at home. I remember picking it up casually. In my memory, the cover looked much as it does today, with its striking red and yellow arrow shapes forming a circle.
For some reason, I still vividly remember my father saying, almost to himself, “That is why Toyota is strong.” Of course, as a high school student, I did not really understand what he meant. Terms such as just-in-time, kanban, and jidoka felt like ideas from a distant manufacturing world.
More than forty years have passed since then.
Prompted by my conversation with the Toyota employee, I decided to read this classic again. I ordered a copy right away and read it through in one sitting. What surprised me on rereading it was how little it had aged. Many people may think of Toyota Production System as a book about just-in-time production or the kanban system. These are certainly important elements. But when I read it again, I felt that the book is not merely about production control methods.
What left the strongest impression on me was its skepticism toward the idea that faster is always better.
Installing faster machines is, of course, not a bad thing in itself. But if only one process becomes faster while the connection with the processes before and after it remains poor, work in progress and waiting time are created. The speed of a local optimization can make the overall flow worse. Ohno makes a point similar to saying that the tortoise can be better than the hare. What matters is not a burst of speed at a single moment, but the ability of the whole system to keep moving in a steady rhythm. Read today, this feels like a quiet question directed at our modern faith in technology.
Introduce a new machine. Introduce a new system. Introduce a new AI tool. Then productivity should rise. We are easily drawn into this way of thinking. But the real question may be whether that technology is improving the flow of the whole system.
Today, many companies are working to make use of AI. Writing, research, analysis, preparing materials, responding to emails, creating meeting minutes: AI now allows work that once took people a great deal of time to be processed with astonishing speed. Business automation will only continue to advance.
That is exactly why I feel the Toyota Production System’s idea of jidoka has become important again. Automation means replacing work previously done by people with machines. In the Toyota Production System, however, jidoka is not simple mechanization. When an abnormality occurs, the process stops. Because it stops, the problem becomes visible. Because the problem becomes visible, people can think about the cause and improve the process. In other words, I understand jidoka as a system that enables people to focus on the places where human judgment is truly needed. The same question is being asked in the age of AI.
AI can generate large amounts of output instantly. Documents, emails, analytical notes, and proposal drafts can all be created far faster than before. But the fact that something can be created does not necessarily mean that it should be created. More documents, more emails, more analyses, more proposals: on the surface, it may look as though the volume of work being produced has increased.
But is that really creating value? Even if AI increases the “output of work,” it does not necessarily increase the “output of value.” If organizations misread this point, they may become busier than before while delivering no greater value to customers.
That is why, before introducing AI, we need to think about what constitutes value, what constitutes waste, and where people should make judgments. This is not only a question for manufacturing. It applies equally to sales, development, administrative departments, service businesses, and small and medium-sized enterprises. Work increases, yet results do not follow. Meetings and documents multiply, yet decisions do not become faster. These things can happen in many organizations.
In management, what matters is not simply introducing the latest technology, but continuing to ask what is value and what is waste. It also matters to ask those questions within the actual flow of work on the ground. Taiichi Ohno’s thinking later spread around the world as lean management and influenced fields far beyond manufacturing. Why did ideas born on the factory floor spread so widely?
I think it is because the questions at their center are universal.
What is value for the customer? What activities do not create value? How can we prevent problems from being hidden? How can we draw out the wisdom of the people on the front line? How can we build a system for trying, learning, and improving in small steps? These are questions business leaders in the age of AI cannot avoid. AI can become a powerful tool, but a tool is still only a tool. If what we want to achieve and what we consider valuable remain unclear, AI may not reduce waste at all. It may simply increase waste at high speed. Perhaps Toyota Production System, written half a century ago, still feels new because it contains a philosophy of management that goes beyond a discussion of technology.
As a high school student, I did not really understand what my father meant when he said, “That is why Toyota is strong.” Rereading the book nearly half a century later, I feel that Toyota’s strength was not found only in advanced equipment or special technology. It came from thinking through what creates value and what is waste, making problems visible, drawing out the wisdom of the workplace, and enabling the whole system to move in a good rhythm. Perhaps the accumulation of these practices is what has supported Toyota’s strength for so long.
Precisely because we now live in the age of AI, there is meaning in reading Taiichi Ohno again.
That is how I feel.