Six Sigma and Change Management
Every
institution is vulnerable, no matter how great.
No matter how much you’ve achieved, no matter how far you’ve gone, no
matter how much power you’ve garnered, you are vulnerable to decline. There is no law of nature that the most
powerful will inevitably remain at the top.
– Jim
Collins6
Introducing Lewin’s Change Model
As
Collins eloquently writes, if a company does not change and adapt to a changing
environment, it will likely die. Managing
change is the main role of a leader. Jack
Welch is well aware of this, and made this an important point in his
definition. Since Six Sigma can and
should be used as a mechanism for change, it is logical to see its crucial role
in developing leaders.
Let
us look at this idea of leadership and change management a little further. One of the cornerstone models for
understanding organizational change was developed by Kurt Lewin back in the
1940s, and still holds true today. His model, known as Unfreeze – Change –
Refreeze, refers to the three-stage process of change he describes. Lewin, a
physicist as well as social scientist, explained organizational change using
the analogy of changing the shape of a block of ice.7 In order to
change the shape of a cube of ice into a pyramid of ice of equal volume, you
have to unfreeze it, place the water into a new mold, and refreeze it. On both
ends of the change, the process is held in equilibrium, with some forces
exerting helpful pressure, and others negative pressure. This equilibrium can be depicted using a
force field analysis.
Six Sigma seen through Lewin’s
model
The Six Sigma methodology can
very intuitively be framed following Lewin’s change model.
Define/Measure
The performance of a culture,
before a Six Sigma deployment, is driven primarily by the amount of inertia it
experiences, i.e. a level of comfort with “status quo.” This status quo often leads to sub-optimal
processes, processes that are “good enough” and characterized by significant
waste (muda) and excessive variation. As
the leadership team becomes aware that increased profitability could be
achieved with better processes, and business analytics yield new information
and insights, these helping forces may lead to a decision to improve
operational excellence. One way to
accomplish this is through a Six Sigma deployment. Not only are these forces seen at the
organizational level, but they are also present at the beginning of most Six
Sigma projects. Status quo, muda and
variation dictate a process’ capability, while a financial analysis (linked to
profitability) and baselining of the process (read analytics) help describe
opportunities. Change begins with a
culture that challenges the status quo.
If status quo is accepted, waste and process variation will be
tolerated. There will be no reason or
incentive to address short-comings, if short-comings are even recognized. Lean Six Sigma is most effective and durable
when it builds on an underlying culture that demands continuous gains in
efficiencies. Such a culture typically
exhibits a bias for improvement activities, or to use Deming’s words, “a
constancy of purpose toward continuous improvement”
Analyze
As the team (leadership or
project) becomes discontent with status-quo it begins the process of unfreezing
the existing process. Just because this
is “how we’ve always done it,” does not mean that the process cannot be
improved. At this stage, the process is
subjected to a root cause analysis. The
team can use qualitative tools, such as brainstorming, Ishikawa and affinity
diagrams, cause and effect matrices, and failure modes and effects analysis. It
may also use Six Sigma’s quantitative arsenal, with weapons such as box plots,
dot-plots, histograms and other graphical tools, and a plethora of hypothesis
tests, to include correlation and multiple regression analysis. At this point, the process assumptions should
have been shaken to their core, achieving an unfreezing of the process, and
identifying new hypothesis and theories about how its performance is driven. As we now want to move from correlation to
causation, we are ready for experimentation.
Improve
It is in this stage that we
really begin to improve the process. Deliberate experimentation, usually
through design of experiments enable to team to identify true cause and effect
relationships, and build models that optimize the performance of the process
the team is trying to improve. Indeed,
we are changing the process through improvement, molding it into its new shape.
Control
Quality (Solution) = Impact
(Solution) x Permanence (Solution) (Equation 2.1)
As seen in equation 2.1, the
impact of the solution is determined in the Improve Phase, while its permanence
is greatly influenced in the Control Phase; the Control Phase is a key aspect
of Six Sigma. In this step, the team is
truly attempting to refreeze the process at its new and improved level of
performance. The forces present at this
stage differ of the forces before the change effort. Key Six Sigma tools and techniques are
employed to that end. Control Plans (CP)
identify, critical input by critical input, the specifications at which the process
need to be set, and what activities need to be conducted on an on-going basis
at predetermined intervals. Mistake
proofing (Poka Yoke) relates to the robustness of the solution, i.e. the
propensity for a mistake or error to occur.
Usually through design consideration, the ability for a defect to
manifest itself needs to be minimized.
Finally, on-going monitoring of the process can be achieved through
Statistical Process Control (SPC), a process developed by Shewhart at Bell
Labs, and refined later by W.E. Deming.
As these forces are put into place, great care needs to be taken of not
introducing complexity and over-burden (muri) into the process, as these are
hindering forces that will make sustaining the improvement more difficult. As Pascal Dennis writes in Getting the Right Things Done,
“Complexity reflects a primitive state; simplicity marks the end of a process
of refining.”8
References
6.
J. Collins, “How the Mighty
Fall,” HarperCollins Books, 2009
8.
P. Dennis, “Getting the Right
Things Done,” The Lean Enterprise Institute, 2006
