TPS’s Operational Paradox

A quest for ultimate efficiency

Published: Monday, July 19, 2021 - 12:03

Recently, I came across an interesting insight at Toyota’s website. I was taken aback by the first sentence of this paragraph: “Eventually, the value added by the line’s human operators disappears.”

The complete paragraph is shown below:
“Eventually, the value added by the line’s human operators disappears, meaning any operator can use the line to produce the same result. Only then is the jidoka mechanism incorporated into actual production lines. Through the repetition of this process, machinery becomes simpler and less expensive, while maintenance becomes less time consuming and less costly, enabling the creation of simple, slim, flexible lines that are adaptable to fluctuations in production volume.”

Generally, we talk about increasing the value-added activities in lean or the Toyota Production System (TPS). Here, Toyota seems to be stating a paradox: We should get so good at what we do that we do not add value anymore. We keep finding better and better ways at doing what we do so eventually the process doesn’t necessarily need us to do that job.

The website details the ideas of TPS, mainly jidoka, which is the idea of building in quality so if a defect is produced, the line stops automatically. I have talked about it on my website before, here and here.

Toyota is advising us to make the operations as simple as possible. We are advised to remove the complexity of the operation. The operator doesn’t have to face unwanted complexity. This complexity should be absorbed by the engineers or management designing the assembly line or the operation. This is an idea similar to Tesler’s law that I have discussed before. Before we can implement the ideas of jidoka, we need to make the operation as stable as possible by avoiding unwanted variation from the operations. By doing this, multiple machines can be handled by one operator.

The paradoxical message might seem to be promoting automation. However, it’s is not that simple. Toyota focuses on work done by hand. The website states:
“The work done by hand in this process is the bedrock of engineering skill. Machines and robots do not think for themselves or evolve on their own. Rather, they evolve as we transfer our skills and craftsmanship to them. In other words, craftsmanship is achieved by learning the basic principles of manufacturing through manual work, then applying them on the factory floor to steadily make improvements. This cycle of improvement in both human skills and technologies is the essence of Toyota’s jidoka. Advancing jidoka in this way helps to reinforce both our manufacturing competitiveness and human resource development.”

The emphasis on doing the work by hand ensures that we understand all the aspects of the operation. Even if a robot is doing the work, it has to be most efficient. This allows for maximum flexibility. The robot imitates a human activity, whether it’s to grab, move, or transform something. While most companies strive for automation, Toyota focuses on simpler activities that might be done with simple machines rather than state-of-the-art robots. The push is to simplify the operation even for a robot!

The manufacturing world must adapt to ever-changing demands, and this means that the assembly lines or the operations will have to be changed as needed. The production environment has a lot more variation than what we can tackle. Thus, the goal is not to get stuck with a monument of expensive, large automation but rather to rely on simple and small machines or robots that can be easily moved or modified as needed to meet the demand. The website continues:
“Human wisdom and ingenuity are indispensable to delivering ever-better cars to customers. Going forward, we will maintain our steadfast dedication to constantly developing human resources who can think independently and implement kaizen.”

We should do our jobs so that we can keep “dehumanizing” activities and thereby have more time to focus on making more improvements. By “dehumanizing,” I mean that we should keep improving our work so that we’re not engaged in repetitive activities that can be done by a machine. The more time we spend on making improvements, the more efficient and effective we become. The machine can be viewed as a closed system. It keeps doing what it is programmed to do. When we interact with the machine, we provide it with new information that allows it to do something new.

Taking this idea of the paradox further, in an ideal world, when we do our jobs effectively, we are engaging in eradicating our jobs altogether. For example, a doctor should be engaging in activities to create conditions where a doctor is no longer needed.

I will finish with Taiichi Ohno’s wise words:
“It is easy to remember theory with the mind; the problem is to remember with the body. The goal is to know and do instinctively.”

This post is also available as a podcast here. Stay safe and always keep on learning.

First published on the Harish’s Notebook blog.

About The Author

Harish Jose

Harish Jose has more than seven years experience in the medical device field. He is a graduate of the University of Missouri-Rolla, where he obtained a master’s degree in manufacturing engineering and published two articles. Harish is an ASQ member with multiple ASQ certifications, including Quality Engineer, Six Sigma Black Belt, and Reliability Engineer. He is a subject-matter expert in lean, data science, database programming, and industrial experiments, and publishes frequently on his blog Harish’s Notebook.