I love talking to people involved in lean. Whether they work on the shop floor or in plant management, in distribution or in administration, they are generally happy to describe the process improvements that they've made, and eager to share the story of their "journey." Their enthusiasm and willingness to embrace change are rare in our workaday world.
If you ask people who are working at such activities what lean production or lean material handling means to them, you will hear a hundred different answers. Most will start with some description of the Toyota Production System, just-in-time delivery, pull production or making material flow. Their words soon turn to their own experience, how they've reduced setup times to speed cycle time, implemented workcells to shrink work-in-process inventory, introduced five S principles to organize the workplace and make the workflow more visible, and how they've used valuestream mapping to identify value-adding and non-value-adding activity.
Such descriptions and techniques don't always translate well for people outside of manufacturing. But as recent articles have shown, lean's process improvement focus can be equally effective at increasing a hospital operating room's utilization rate, or reducing the cycle time of a loan approval process, or speeding material flow through a mail sorting operation (See the Canada Post story on page 26).
I asked an academic friend who has spent a great deal of time studying and writing about the topic how she defined lean. The philosophy starts with waste elimination and continuous flow, says Dr. Rachna Shah, an assistant professor of operations management at the University of Minnesota's Carlson School of Management. Basic principles include an understanding of the value stream, setting up pull systems and striving for continuous improvement. The academic literature also defines lean in terms of four fundamental characteristics: standardized work, seamless linkages, simple and direct work pathways, and process improvement based on the scientific method.
"If you think about lean it's all about variabilityreduction," says Dr. Shah. "By standardizing work you're eliminating variability in the way the work is performed." Direct and unambiguous linkages between people doing the work eliminate uncertainty over who has done what work at each process handoff. Simple and direct pathways eliminate variation in material flow. The scientific method's step-by-step procedure, starting with making observations and gathering data, eliminates variability in problem solving.
What's missing from these descriptions, says Shah, is how these companies approach learning. Not only do the most effective lean organizations teach employees what to do and how to do it, they teach people why they must do the work a certain way. Understanding why means employees can see the relationships between cause and effect, between actions and outcomes, how one person working on an assembly line or picking product in a warehouse impacts customers immediately downstream, as well as the ultimate customer.
Powered by non-stop training and learning, I think this understanding is one of the reasons lean advocates tend to be so zealous in their pursuit of perfection. They have emerged from a world of darkness where everyone only did the job they were told to do. Because they understand the why people are more engaged in their work, and they are able and willing to contribute ideas for improvement.
"If we could somehow manage the manifestation of why in the norms and cultures of our organizations, I think we can all achieve higher performance like Toyota does," Shah believes. What material handling manager wouldn't want that?