What’s Lean All About?

I’ve been working on refreshing and enhancing our learning resources related to Total Productive Maintenance, or TPM. People may be familiar with these letters as they appear in kaizen bursts on a value stream map. In this context, TPM is often shorthand for activities to reduce equipment downtime or even do basic daily preventive maintenance. However, there’s much more to a comprehensive TPM program.

In fact, in terms of its scope, breadth of tools, change management approaches, and the use of multi-phase deployment, it rivals anything found in the more popular Lean or Six Sigma methods. There’s a great deal of overlap between these three. TPM also offers many insights and practices unique to equipment-intensive processes. While TPM is often deployed as a tactic supporting some brand of operational excellence, it began as its own comprehensive strategy. Thinking through how to best present TPM’s various ideas and approaches led me to ask some broader questions.

TPM Is Not All About Flow

Some say lean is all about making value flow smoothly to the customer. When we flow faster, the time, energy, and cash we invested in a system comes back to us faster, ideally with some profit on top. Attempting flow helps us to identify inefficiencies, transaction costs, incapable processes, physically disconnected processes, or other barriers. Once we establish flow, a stoppage in flow signals an abnormal condition needing attention. In lean thinking, flow can be both a means and an end.

Discrete manufacturing operations have the option to flow or not to flow. They can disconnect processes, choose to work in batch and queue, or put miles of distance between sequential processes steps. This happens for various reasons. It may be because we don’t know any better. Or because our metrics lie to us, or because our financial decision-making horizons are very short, leading us to pursue the lowest offshore piece price. I would venture to say that a majority of discrete manufacturers today are striving to remove barriers to flow. When equipment downtime is one such barrier, TPM activity can help.

In many contexts where TPM is adopted, flow is already a given. In continuous process industries such as chemical refineries, some pharmaceuticals, or fast-moving consumer goods, flow is a basic condition. The high-cost fixed assets are often mechanically connected by pipes, conveyor belts, or other means. In such a context, the TPM challenge is not to create flow, but to reduce losses and keep the flow going.

The Emphasis on Stability

Because of the need to produce good quality safely at high speeds, much of the emphasis of TPM is on building stability. Notably, it does this both at the equipment level and at the level of the operating system. The idea of TPM creating equipment stability is intuitive. Focused improvement activities reduce the 6 big losses such as idling, long changeover times, or machine breakdowns. Machine operators contribute to keeping equipment in good condition through basic daily autonomous maintenance actions. Planned Maintenance helps to predict and prevent breakdowns.

The notion that TPM builds stability in the operating system itself is a bit meta. It requires some explanation. In short, many of the pillars of TPM interact with each other to strengthen the organization in total. This includes developing people, clarifying responsibilities, enhancing cooperation, improving equipment design, and more. Although the pillars of TPM are often depicted as columns of a Greek temple, a more accurate picture would be two sets of interlocking puzzle pieces.

Autonomous Maintenance is not possible without reasonably stable processes, which the Focused Improvement pillar activities enable. Once operators do Autonomous Maintenance, this frees up the maintenance staff to do more high-value, proactive, and Planned Maintenance. The Early Equipment Management pillar ensures that we design, acquire and install new equipment to be easier to maintain as well as highly reliable. The Education & Training pillar supports all of these, as well as helps to expand TPM into areas of quality, safety and environment, and administrative functions. When leaders commit to TPM and take the T in TPM seriously, they find themselves building total organizational stability.

Lean Is All About…Flow?

Perhaps because our modern understanding and coining of the term lean management comes from the automotive industry, we’ve been led to believe that lean is all about flow. Lean is often boiled down to the five steps of let the customer define value, map the value stream, pull, flow, and pursue perfection. The early success stories from Wiremold, Danaher, United Technologies, and others often involved stories of flow. Kaizen teams picked up and rearranged all of the machines in a plant over a weekend, creating flow and leading to dramatic improvements.

Where are the stories of stabilization? These are harder to chronicle because the author doing research for a book can’t visit a few week-long kaizen events to get the gist of TPM. It’s slow, dirty, detailed work. The before and after photos, and the stories of how they got there, contain less drama. The flashiness and speed of change in the “lean is flow” story may appeal to a certain type of business leader.

And yet the lack of stability is one of the main reasons that improvements from kaizen events or even larger-scale value stream transformations fail to sustain. Lean can be all about flow, as long as we don’t forget that stability is the foundation. It’s also true that when we make it all about stability and pursue equipment reliability or high output without a vision of customer-focused flow and pull, this leads to sub-optimization and higher overall cost.

What’s Lean All About?

“We’ve moved beyond lean is all about flow,” some may say. Lean is all about continuous improvement, problem-solving, and experimentation. “No, no. Haven’t you heard? Lean is all about the people.” Others may say. The point of using flow to expose and solve problems is to develop people who can meet tomorrow’s challenges, whatever those may be. “Ah, but surely, isn’t Lean all about turning these skills into habits and routines?” Give it a couple of years, and someone will try to convince us that Lean is all about something else.

The answer to “What’s lean all about?” has changed over time. The question of what lean is “all about” comes from people’s need for simple answers. An idea like “lean is all about flow” is easier to communicate than long explanations of how various pillars and principles interact.

In terms of marketing and popularizing an idea, “lean” has done extraordinarily well. However, the brevity and apparent simplicity of this idea often come at a cost. It’s hard to put into practice. The danger is when “it’s all about” becomes dogma, we stop thinking critically, face a situation where the solution is not flow, we give up on lean and start looking for the next thing.

What’s lean all about? When asked questions like this, I always go back to Deming’s system of profound knowledge. To paraphrase, he said good management, a.k.a. lean, is all about four things: the appreciation for a system, knowledge about variation, theory of knowledge, and knowledge of psychology. This profound knowledge encompasses flow and stability, quality and reliability, problem-solving and improvement, and people. This was a lot to digest, market, and popularize.

There may not be one best answer. Certainly there are many inferior ones. It’s up to each of us to learn as much as we can about all of the above, and figure out exactly what works in our own unique context.

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