People interested in improvement have been having the same arguments throughout my 25 plus year career. And, I am certain similar things went on before. Let's just revisit the last 20 years and the major improvement initiatives, that I have done:
Quality Circles.....involve your people, they know! Most companies got some good out of this, however the literal translations taken back from Japan by the Lockheed team were somewhat misguided. They did not see how Circles fit with in the larger process. Basic idea of involvement though is on target.
Total Quality Management (coined by Fiegenbaum) Brought forth the idea that high quality is actually cheaper, not more expensive. Again organizations for the most part received some good from this, most did it rather programmatically and hoped that once the program was implemented they could move on to other things. Customer Quality Management kind of added to this to give a customer focus spin on things. Did help people to see that customer requirements exists at several levels (specifications, expectations, and delighters) also helped people realize that multiple customer groups exist and some of them have conflicts with other constituencies (e.g., purchasing, engineering and operations).
SPC (father Deming) Gave the world (and me in particular) a process centric view of the world. The whole concept of reducing "variability", focusing on key points, etc. Ideas well known by statisticians, but like a new science to the rest of us. Good things came from it, but it was never totally embraced by general management. Perhaps too technical and not sexy enough.
Reengineering (actually grew out of SPC.....Hammer got the fame, but a number of people were practicing this, prior to his book) Took the idea of processes and applied them to the whole business. Deming talked it, but Hammer gave a better (i.e., easier to see picture) of how these concepts applied to overall business practices and processes. This really sounded cool and was embraced. Unfortunately much of the focus was on getting smaller (reducing cost, not growth) and management's support systems to sustain change (communication, accountability, measurement, etc.) were largely ignored.
Six Sigma Coined and started in a big way at Motorola in the early 80s. Evolved into a "hot" sexy, for the moment, new tool. Great tool for looking at complex process interactions. Really takes SPC to the next level, it's SPC with a goal. Very analytical approach, hard data driven. Where measures can help things improve this is a wonderful tool.
Theory of Constraints (Goldratt) Don't wish to over simplify this, but it's largely find and eliminate the bottlenecks and you increase capacity. This is a cool thing to do if you can use the new capacity. The whole idea that improvements in non-bottleneck processes do not increase capacity (although they may reduce costs). Cool book, great story, limited embracing by the management world. Seen as a manufacturing thing, although the Jonah's are trying to expand it now into the larger process perspective. Opportunities exist in engineering and the sales ordering process as well as other areas.
Lean Manufacturing, lean thinking, Flow...Lean was coined by Womack and Jones, they are now trying to foster the concept of the "lean enterprise" vs just production floor, difficult to regroup though after the horse is out of the barn. More visual approach, use of Kaizen, continuous movement, eliminate sitting and waiting, use of Ohno/Shingeo waste emphasis. Took Shoenburgers (sp?) work from the 80s and expanded on the use of production cells. Neat stuff, sounds sexy, too bad they did not start with the words "lean enterprise." (Flow by the way comes from Mihaly Csikszentmihaly...25 cents to anyone who can pronounce it that has not met him).
Other tools/techniques bounced around the periphery of improvement: Quality Function Deployment (QFD), Kaizen as a stand alone, Time Management (Stalk), Hoshin Planning (i.e., manage the exceptions a little more closely), Cost of Quality (Crosby), post-phonement strategies, managing the white space, etc. HP did a lot with post-phonement and hoshin.
All of this is exciting stuff! The person who said that it is people who compete, not the tools hit it right on the mark. All of these concepts focus on a few basic concepts. Words that we have all used. We need to do it 1. Cheaper, 2. Better, 3. Faster and 4. create more meaning in our work. Most companies/organizations say they want to do these four things. However only a few really focus on the 4th element.
A Motorola executive once told me years ago, that if they could go back to go and only focus on one thing it would be, "time." I tend to agree with that. Although, you can't be nuts about it. We can all take any one of the above tools and implement them to such an extent that we are doing goofy things and contributing more problems then solutions. So every tool needs a sense of balance. The other thing we need to do is to quit compartmentalizing the basic concepts. Lean enterprise would have been so much cooler than lean manufacturing because it focuses to a greater extent on connecting the parts.
As Deming, Juran, Ackoff and countless others have pointed out, everything is part of a process. It all has to work together. We cannot optimize every subcomponent and have the process work, the pieces need to work together. All of the tools above offer different perspectives. Each of them have their own respective strengths and weaknesses. If we get all wrapped around the axle defending our one tool, we lose sight of the overall purpose. If there was only one way to do this stuff, we would all do it. Fortunately for us there is not one way. There are trade-off's for every path. If we go this way we get a little more of this, but not that. If we go another way, the same thing.
That is what makes this work so exciting. There is no "answer." But there are one heck of lot of good ideas. For me, the most exiciting part is seeing people's perspectives change and people literally grow before your eyes as they make change happen. I also enjoy connecting the parts, so that the things happening in operations, connect a little better to engineering, a little better to the customer and general management's begins to see the connections, interplay and trade-offs a little more clearly.