We often speak about the two pillars of the Toyota or Lean system, and when doing so we think of the two well-known pillars of just-in-time (JIT) and built-in quality (jidoka). JIT thereby focuses on manufacturing only the necessary products, at the necessary time, in the necessary quantity by deploying pull flow (kanban), one piece flow and leveling. Jidoka, built-in quality, or autonomation focuses on quality control by stopping the process when abnormalities are detected based upon elements such as standardized work and visual control. But is this correct? Where is “Respect for People” in all of this?
1977 already, in the first open publication about the Toyota way, Sugimori and Cho (the later Toyota chairman, at the time working in production control) explained the structure of the Toyota system. They stated that the Toyota system was based upon two main concepts:
- Reduce cost through the elimination of waste, after which they described JIT and jidoka as the way to materialize this concept.
- Make full use of the workers’ capabilities, which they referred to as the respect-for-human system.
More recently, the Toyota Way is also described as being based upon two very similar pillars, viz., continuous improvement (with the three keywords of challenge, kaizen and genchi genbutsu) and respect for people (with the two keywords of respect and teamwork). In this sense, the Toyota Way in fact represents a very good example of a true socio-technical system.
Lean’s “Respect for People” Pillar
The “respect-for-people” system, at that time, was described as allowing all associates to display in full their capabilities through active participation in running and improving their workshop. The original concept included four elements, that I find more concrete than the more recent illustration using keywords like respect and teamwork:
- Elimination of waste movements by workers.
- Consideration of workers’ safety.
- Increasing autonomy by entrusting workers with greater responsibility and authority.
The “respect-for-human” pillar is also perfectly aligned with the concept of the elimination of waste. The idea is that “workers may realize their work worthy only if the labor of diligent workers is exclusively used to raise added value of products”. This is also behind the first element of the “respect-for-human” system. So, eliminating waste like eliminating material handling activities, separating man and machine to enable workers to work on multiple machines that add value, and having machines stop when defects are detected, are also seen as activities that respect the human.
Automating and unmanning dangerous, unhealthy, and monotonous operations is not seen as laying off people, but as part of the “respect-for-human” system, considering its physical and mental health.
The jidoka approach as well is seen as being perfectly aligned with the “respect-for-human” system. Then jidoka prevents situations that are out-of-standard and by definition lead to work that is more difficult, more risky, takes place in areas or under conditions that are not ideal for the worker, the product and the equipment. Jidoka therefore not only leads to better quality and less waste, but also to improved safety and less incidents and accidents.
Toyota firmly believes that making up a system where capable workers can actively participate in running and improving their workshops and be able to fully display their capabilities would be the foundation of an environment with respect for the human of the highest order.
This basic thought is also behind things like the andon cord or button (giving all workers the right to stop the line), visual control (enabling all workers to detect problems) and the separation of man and machine (as it should not be the machine that operates the person, but the person that operates the machine). At the same time it is also behind the kanban system whereby the actual authority for decisions of job dispatching and overtime is delegated to the shop floor.
Lastly, the respect-for-human” system allows all workers to take part in making improvements. Any employee at Toyota has the responsibility and the right (authority) to make an improvement on the waste he has found.
A Stable Lean Temple
Summarized, the Toyota Production System as it is often illustrated by the two pillars of JIT and jidoka is only a part of the whole picture. Next to the TPS there is the pillar of “respect for human” or “respect for people”. So maybe it is a good thing to introduce a third pillar to the Lean temple to recreate the correct balance between JIT, jidoka and respect for people. Then to create a stable temple — to continue to use this metaphor — in any case the building will be far more stable with three pillars than with two. A Lean temple with three pillars is like a three-legged stool… impossible to wobble…