In Part 2 of this series from Appendix 1 of Epiphanized, Bruce Nelson now discusses Lean and Six Sigma followed by the concept of Focus and Leverage.
Lean
Much has been written
about Lean over the past several years, but its basic philosophy is centered on
a whole-systems approach that focuses on the existence and removal of
non-value-added (NVA) activities within a process or system. These NVA
activities are characterized as waste in the Lean vernacular. As an
improvement initiative, Lean teaches you to recognize that waste is present
within every process and that we should take extreme actions to either
eliminate it or significantly reduce it. The entire premise for doing this
action is to facilitate a flow of value through the entire process. If this is
true, then it begs the question—What is value?
There have been many attempts to
define value, but the best definition is based on the customer value and
not the producer value. In its simplest terms, value, is whatever the customer
feels good about paying for. Customers know what they want, when they want it
and how much it is reasonable to pay for it—so in the long run, value clarifies
itself. Lean has become recognized as one of the most effective business
improvement strategies used in the world today, but if this is so, then why are
so many Lean implementations failing at such an alarming rate? In this case,
failure implies the inability to not only achieve, but also sustain, the needed
effort.
Six Sigma
Like Lean, much has been
written about Six-Sigma methods and the now infamous acronym DMAIC. Whereas
Lean is attempting to remove non-value-added and wasteful activities, Six Sigma
is attempting to remove unnecessary and unwanted variation. Six Sigma uses the
road map Define, Measure, Analyze, Improve and Control (DMAIC) to seek
out sources of variation, and through various statistically based tools and
techniques, attempts to limit (control) variation to the lowest possible
level. The professed power of Six Sigma lies in the disciplined structure and
use of the tools and techniques.
However, this supposed power sometimes ends up being a detriment
to some companies because in many instances they will experience enormous
information overload, coupled with a failure to launch the information into
viable solutions. In essence, these companies are suffering from analysis
paralysis. Like Lean, many Six Sigma initiatives have failed to deliver true
quantifiable bottom line improvements and, therefore, have been abandoned. Six
Sigma can be difficult to employ. It is heavily dependent on mathematics
(statistics) and formula derivatives that quite frankly most people do not
enjoy or involve themselves with. At times is seems as if you need to call
Merlin the magician just to get started.
There is also popular hybrid of Lean and Six Sigma known as
Lean-Sigma which, as the name suggests, is a merger of the two initiatives.
The primary assumption of Lean-Sigma is that eliminating or reducing waste and
variation in the system will lead to major cost reductions. It seems to make
perfect sense that if each initiative delivers its own separate improvement,
then combining output from both of them should optimize the process and result
in a double-dip reduction in cost. However, in the final analysis, the primary
functions of Lean and Six Sigma are aimed at cost savings.
Saving money is
indeed a strategy, but it’s just not an effective strategy for making money.
The overall issue is not with either one of these methodologies, but rather the
belief that the way to increase profitability is through cost reduction. Cost
reductions have implied mathematical limits, and once those limits are
encountered, the improvement effort stops or slows down significantly. Consider
this—have you ever heard of a company that has actually saved themselves into
prosperity? If cost reduction is not the answer, then what is the best route to
profitability?
Focus and Leverage
From what has been
stated so far, you might think we have a negative view of Lean and Six Sigma,
but such is not the case. In fact, TOC by itself cannot deliver sustainable
bottom-line improvement. But it does provide the needed global system focus,
and that focus is paramount to facilitating organizational growth. In fact, the
primary reason why Lean and Six Sigma have failed to deliver acceptable ROI is
they try to improve everything all at once, rather than focusing on the most
important leverage points. They promote improvement because they can, and not
because they must. It’s like trying to solve world hunger—it’s a tough job when
you try to do it all at once. So let us discuss leverage points and what they
mean.
Leverage
The foundational concepts of TOC can be presented in a simple, but
understandable way as a reference environment. If you understand the
reference, you understand the concept. If we use a diagram showing a simple
piping system with the primary goal of delivering water, then the reference is
defined. By presenting the concept in this format, the basic principles will be
much easier to comprehend for people who have not yet had any experience with
the Theory of Constraints.
Figure 1: The Piping System
Figure 1 describes the piping system with different diameter pipes
connected together supporting the water flowing through this system. The water
flows from left to right from Section A through the entire length of the system
until it exits at Section G. If you were given this water system and asked what
you would do to increase the flow of water, or the throughput of water, through
this system—how would you answer the question? For most responders, the answer
would be to increase the pipe diameter of Section C since it is the choke
point, or bottleneck, or constraint of this system. If you increased the diameter
of any other pipe section, it would have absolutely no effect on the throughput
of water through this system.
If you were asked how
much you would increase the diameter of Section C—how would you answer that
question? Most responders would answer by saying that the increased diameter of
the Section C pipe would be determined by how much more water the system needed
to deliver (loads on the system). So in order to satisfy the need (demand) for
more water, you must have some type of metric for how much more water is needed
(increased loads on the system). Let’s say that you increased the diameter of
the pipe in Section C to the same diameter as the pipe in Section D. What if
the measured throughput of water out of Section G was still not enough to
satisfy the new demand—what then? The new focus for system improvement would
shift to the new constraints (the constraints have moved) which are now both
Sections A and E. These two sections become interactive with each other. The
diameter of these two pipes now becomes the new system constraint, and they
need to be improved to meet the increased demand. So how does all of this apply
to the real world?
Focus
The basic principles of understanding constraints are all around
us. For example, instead of using the piping system to demonstrate the
constraint, we could have substituted an electric circuit with different sized
resistors and measured the flow of electricity through the circuit. The
resistor location with the highest resistance to electrical flow would be the
equivalent of Section C in the piping diagram. You could easily demonstrate
that the flow of electricity through that system is completely dependent upon
how much more electrical current was needed to satisfy the demand. And in order
to increase the electrical output, you need to reduce the resistance of the
resistor that was limiting the electrical flow.
Figure 2 is another simple visual example of the same concept.
Here we have a four-step process used to produce some kind of product or
service. If we apply the same systems thinking and ask the same series
of questions about this system, then we can effectively conclude that Step 2,
at 17 days, is the process that is limiting the output from this system. By
understanding this concept you now know where to focus your improvement
efforts. Improving any other process in this system, except for Step 2, yields no system improvements at all. Globally, the system will improve only when Step 2 requires less time.
Figure 2:
The Process
In my next posting, Bruce will tie the three improvement methodologies together.
Bob Sproull
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