The Human Side of Lean

Introduction

The Human Side of Lean Manufacturing refers to those elements of lean and corporate culture that impact people's attitudes, their interactions with others and their interaction with the technical processes. It is important because people are part of the system and part of the process.

It has taken well over twenty-five years for Lean Manufacturing to have significant impact in the United States. Even today, it can be argued that most manufacturers talk big but implement poorly. More than anything else, problems on the Human Side are responsible for this tardiness.

Difficulties With The Human Side

One difficulty in discussing the Human Side is that it permeates every other aspect of lean, often in subtle ways. It cannot be isolated and addressed as a separate issue.

Kanban, for example seems to be a simple, mechanistic arrangement of stockpoints, cards and rules. However, when employed effectively, kanban positively influences teamwork, setup reduction, quality and other areas of process improvement. These areas, in turn, can make or break the kanban system.

Another difficulty involves the difference between "influence" and "cause." "Cause" means that action A always results in effect B. Influence means that action A enhances or increases the probability of effect B provided that other actions C, D and F also occur with proper proportion and timing. However, result B, still, may or may not occur. We often prefer to think about causes rather than influences.

• Causes are clean, precise, predictable;

• influences are messy, probabilistic, uncertain and conditional.

History of The Human Side

Great leaders from the dawn of history understood it the human side, at least intuitively. In the narrower field of manufacturing, the formal exposition of such concepts dates back at least as far as Lillian Gilbreth in the 1920's as well as the Hawthorne experiments. Eric Trist developed Socio Technical Systems in the early 1950's.

Of W. Edward Deming's famous Fourteen Points, at least eleven related to the Human Side. Then there was Abraham Maslow, Douglas McGregor and many others who contributed over the decades. Most of this early work had little impact outside the classrooms of business schools.

The early Japanese literature on Just-In-Time and Toyota from the 1970's & 1980's emphasized the human side of the system as one of two underlying themes:

1) Eliminating Waste

2) Respect for People.

For a variety of reasons, the "respect for people" aspect of TPS was mostly lost in transference to the West. Actually, much of the systemic nature of TPS was also lost in the translation. Early efforts at applying TPS principles, for example, sometimes focused on "kanban cards" or "Quality Circles" as The Answer with little consideration for SMED, workcells or anything else.

In the case of Taiichi Ohno, emphasis on the human side holds some irony. Ohno was not usually considered a "people person." He was, however, pragmatic. If "respect for people" was necessary for Toyota's success, he was willing to go along. For Shigeo Shingo, the human side seemed to come more naturally. Our article summarizing Spear and Kent's paper, "Decoding The DNA of the Toyota Production System," shows how the underlying corporate culture plays into Toyota's success.

Socio Technical Systems

Eric Trist's work on Socio Technical Systems (STS) provides a framework for understanding the relationships between the technical  and human aspects of Lean Manufacturing. STS views a factory as an interlocking system of causes, influences and effects. Some of which are primarily technical (e.g., plant layout) and others primarily socio or human (e.g.,communication, loyalties or objectives).

Our page on Socio Technical Systems introduces the concept. A subsequent page condenses the concept into Principles Of Socio Technical Design. Further pages show how the principles apply to the conversion of an assembly line to Cellular Manufacturing and the conversion of a functional layout to a cellular layout.

References

SPEAR, Steven and BOWEN, H. Kent, "Decoding the DNA of the Toyota Production System.",Harvard Business Review, September-October, 1999.

DAVIS, Stanley M., Managing Corporate Culture, Ballinger Publishing, Cambridge, Massachusetts, 1984.