What Is Six Sigma?
Six
Sigma actually has its roots in a 19th Century mathematical theory, but
found its way into today’s mainstream business world through the
efforts of an engineer at Motorola in the 1980s. Now heralded as one of
the foremost methodological practices for improving customer
satisfaction and improving business processes, Six Sigma has been
refined and perfected over the years into what we see today.
Six Sigma originates from a 19th
Century mathematical theory, but found its way into today’s mainstream
business world through the efforts of an engineer at Motorola in the
1980s. Now heralded as one of the foremost methodological practices for
improving customer satisfaction and improving business processes, Six
Sigma has been refined and perfected over the years into what we see
today.
No matter the
setting, the goal remains the same: Six Sigma seeks to improve business
processes by removing the causes of errors that lead to defects in a
product or service. It accomplishes this by setting up a management
system that systematically identifies errors and provides methods for
eliminating them.
Those who learn Six Sigma practices achieve designations at each level of accomplishment, including
Green Belt, Black Belt, Master Black Belt and Champion.
The Beginnings of Six Sigma
The process that led to Six Sigma was originated in the 19th
Century with the bell curve developed by Carl Fredrick Grauss. In the
1920s, statistician Carl Shewhart, a founding member of the Institute of
Mathematical Statistics, showed that a process required correction
after it had deviated three sigma from the mean.
Move
forward to the 1970s, when Motorola senior executive Art Sundry
complained about the lack of consistent quality in the company’s
products, according to the 2006 book “Six Sigma” by Richard Schroeder
and Harry Mikel.
According
to the accepted story from numerous sources, Motorola engineer Bill
Smith eventually answered the call to consistently manufacture quality
products by working out the methodologies of Six Sigma in 1986. The
system is influenced by, but different than, other management
improvement strategies of the time, including
Total Quality Management and Zero Defects.
Some of the Major Aspects of Six Sigma
In
an effort to bring operations to a “six sigma” level – essentially 3.4
defects for every one million opportunities – the methodology calls for
continuous efforts to get processes to the point where they produce
stable and predictable results.
Deconstructing
the manufacturing process down to its essential parts, Six Sigma
defines and evaluates each step of a process, searching for ways to
improve efficiencies in a business structure, improve the quality of the
process and increase the bottom-line profit.
Toward that end, the methodology calls for the training of personnel in Six Sigma, including beginner Green Belts,
Black Belts who often head up individual projects, and Master Black Belts who look for ways to apply Six Sigma across a business structure to make improvements.
The
ultimate goal is to improve every process to a “six sigma” level or
better. Does it work? Motorola reported in 2006 that the company had
saved $17 billion using Six Sigma.
Methodologies of Six Sigma
There
are two major methodologies used within Six Sigma, both of which are
composed of five sections, according to the 2005 book “JURAN Institute
Six Sigma Breakthrough and Beyond” by Joseph A. De Feo and William
Barnard.
DMAIC: This method is used primarily for improving existing business processes. The letters stand for:
- Define the problem and the project goals
- Measure in detail the various aspects of the current process
- Analyze data to, among other things, find the root defects in a process
- Improve the process
- Control how the process is done in the future.
DMADV: This method is typically used to create new processes and new products or services. The letters stand for:
- Define the project goals
- Measure critical components of the process and the product capabilities
- Analyze the data and develop various designs for the process, eventually picking the best one
- Design and test details of the process
- Verify the design by running simulations and a pilot program, and then handing over the process to the client
There
are also many different management tools used within Six Sigma. While
there are too many to list, here are details on a few of them.
Five Whys – This is a method that uses questions to get to the
root cause of a problem.
The method is simple: simply state the final problem (the car wouldn’t
start, I was late to work again today) and then ask the question “why,”
breaking down the issue to its root cause. In these two cases, it might
be: because I didn’t maintain the car properly and because I need to
leave my house earlier to get to work on time. The process first came to
prominence at Toyota.
CTQ Tree – The
Critical to Quality Tree diagram
breaks down the components of a process that produces the features
needed in your product and service if you wish to have satisfied
customers.
Root Cause Analysis – Much
like the Five Whys, this is a process by which a business attempts to
identify the root cause of a defect and then correct it, rather than
simply correcting the surface “symptom” of the problem.
Ultimately,
all of the tools and methodologies in Six Sigma serve one purpose: to
streamline business processes in order to produce the best products and
services possible with the smallest amount of defects. Its
adoption by corporations around the globe is both an indicator of and testament to its remarkable success in today’s business environment.
References
http://www.sixsigmadaily.com/what-is-six-sigma/
