Guest Post: 11 Common Misconceptions About Lean
Mark's note: Here's another great vacation guest post by Jeff Hajek:
By Jeff Hajek
Despite having been fairly main stream for going on three decades now, there are a surprising number of misconceptions about Lean. Here is a list of 11 of the top things people misunderstand about continuous improvement.
- Lean means getting rid of inventory. The reduction in inventory is actually the result of Lean, not its method. All of the associated improvements like pull, poka yoke, Standard Work and the like are the tools of Lean that lead to flow and the ability to reduce inventory. Arbitrarily cut inventory and you've got problems. There is a caveat to this. Many practitioners of Lean, myself included, advocate slowly reducing inventory until something breaks. Then you fix that something. Do this enough times, and suddenly, you'll realize that you've got flow.
- Kanbans reduce inventory. Kanbans control inventory, they don't reduce it. In most cases, when kanbans are put in place, there is too much inventory on the shop floor. This results in an initial purge as the proper quantities are established. Because this situation of excess is the most common, it means that kanban does act to reduce inventory the majority of the time. In some cases, though, there might not be enough material on hand to keep a process flowing. A kanban in this situation would actually require adding more inventory.
- Standard Work takes away creativity. People see the structure that Standard Work brings to a process, and the think they are being asked to be robots. Robots, though, are not asked how to improve a process, and they are certainly not invited onto teams to make those ideas a reality. Poorly led Standard Work can be robotic in nature, but good leaders use it to draw creativity out of people.
- Takt time can be changed or measured. Takt time is a calculated number that is based on factors that are generally outside of the control of people on the shop floor. They can seldom change working hours, and they have little impact on demand. It is surprising how many times people talk about changing takt time (misunderstanding what it is), or want to measure it (confusing it with cycle time). Granted, sophisticated operations do start and stop lines based on demand, effectively changing working time available, but the people doing that have a deep understanding of what takt time is. In most cases, though, talk of changing takt time is misguided.
- Lean is about squeezing more out of people. The sales pitch for Lean often extolls reduction in lead times and productivity improvements. Without having seen it in action, it is hard for many people to believe that a team could double output, for example, without working a lot harder. With Lean, though, the only thing that should be squeezed out of people is ideas. Lean, at its heart, is about reducing waste, and it takes the same effort to do a wasteful process as an effective one. The latter just happens to result in getting a lot more done. Normally, when something sounds too good to be true, it is. Lean is an exception.
- Lean makes work easier. This is a myth that is most commonly perpetuated by leaders. They try to sell teams on the premise that Lean will make their workday easier. The truth is that Lean does, in fact, remove waste from processes and eliminates many of the hardest aspects of jobs. The problem with this statement is that the freed-up time is quickly filled by line balancing or process improvement tasks. In many cases, workers go from having a significant portion of their day spent waiting for something to a steady, reasonable pace. This constant motion can feel more tiring by comparison.
- Lean means a reduction in jobs. This might work once. If a leader harvests the gains of process improvement by reducing headcount, there will never, ever, ever be support for an improvement project again. And you can forget about the possibility of having people take on daily improvement on their own. Nobody wants to play a role in costing themselves their job. The right way to capitalize on process improvement is through growth without hiring or through attrition.
- Lean started with Toyota. Toyota did, and does, great things to propagate Lean, but many of the key principles come from much, much earlier. The concept of separating people from machines, for example, came sometime in the 700's A.D with the advent of windmills. People no longer had to grind grain by hand. That concept, of course, was refined through the use of jidoka when Toyota was still Toyoda and making textiles. Similarly, other improvement ideas came from a variety of historical sources. For example, Eli Whitney and his interchangeable parts predecessors pioneered the focus on quality from the perspective of conformance to specification. Henry Ford and, centuries earlier, the Venetian Arsenal, strove to achieve flow via assembly lines.
- Lean is focused on applying tools. People hear about Lean and immediately think of 5S, the 5 Whys, the 7 wastes, kanban, Standard Work, and andon lights. These tools are great, but they flounder without a strong structure. Policy deployment establishes priorities. KPIs track ongoing progress. Daily management sets up immediate targets. Without a Lean management framework, the tools will fall short of their potential.
- Lean is for the shop floor. There are still a great number of people who know little about Lean. When they do make first contact, more likely than not their initial information will be oriented on manufacturing. Fortunately, this myth is being debunked regularly. The Lean Office and Lean Healthcare are both now common buzzwords. It is not as hard as it once was to convince people to try kaizen in the back office.
- Lean is here to stay. Like all management systems, the term “Lean” as we know it will fade into obscurity. I don't know whether it will last another 10 years, or another century. Eventually, though, something will replace it. Don't do things because it is the Lean way to do things. Do them because it makes processes better and gets you closer to your goals. Remember, Lean is a means to an end. It is not the end.
There are undoubtedly more misconceptions, but this list should highlight the point that Lean is hard and takes relentless study and practice to do it well. Do your research, but hone your craft in the gemba by putting your lessons into practice. There are few things that can break a myth like firsthand experience.
This article was written by Jeff Hajek, the author of The Continuous Improvement Companion, an online Lean reference guide with 450+ entries, including 38 Lean terms on PDFs (296 total pages) and 26 forms that you can download. Many of the terms in this article are explained in detail in this guide.