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Contents
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The
Six Sigma Revolution
By Thomas
Pyzdek, author of The
Six Sigma Handbook
Why
Six Sigma?
For
Motorola, the originator of Six Sigma, the answer to the question "Why
Six Sigma?" was simple: survival. Motorola came to Six Sigma because
it was being consistently beaten in the competitive marketplace by foreign
firms that were able to produce higher quality products at a lower cost.
When a Japanese firm took over a Motorola factory that manufactured Quasar
television sets in the United States in the 1970s, they promptly set about
making drastic changes in the way the factory operated.
Under Japanese management, the factory was soon producing TV sets
with 1/20th the number of defects they had produced under Motorola
management. They did this using the same workforce, technology, and designs,
making it clear that the problem was Motorola's management. Eventually,
even Motorola's own executives had to admit "our quality stinks,"[i]
Finally,
in the mid 1980s, Motorola decided to take quality seriously. Motorola's CEO at the time, Bob Galvin, started the company on
the quality path known as Six Sigma and became a business icon largely
as a result of what he accomplished in quality at Motorola. Today, Motorola
is known worldwide as a quality leader and a profit leader. After Motorola
won the Malcolm Baldrige National Quality Award in 1988 the secret of
their success became public knowledge and the Six Sigma revolution was
on. Today it's hotter than ever.
It would
be a mistake to think that Six Sigma is about quality in the traditional
sense. Quality, defined traditionally as conformance to internal requirements,
has little to do with Six Sigma. Six Sigma is about helping the organization
make more money. To link this objective of Six Sigma with quality requires
a new definition of quality. For Six Sigma purposes I define quality as
the value added by a productive endeavor. Quality comes in two flavors: potential quality and actual quality. Potential quality
is the known maximum possible value added per unit of input. Actual quality
is the current value added per unit of input. The difference between potential
and actual quality is waste. Six Sigma focuses on improving quality
(i.e., reducing waste) by helping organizations produce products and services
better, faster and cheaper. In more traditional terms, Six Sigma focuses
on defect prevention, cycle time reduction, and cost savings. Unlike mindless
cost-cutting programs which reduce value and quality, Six Sigma identifies
and eliminates costs which provide no value to customers: waste costs.
For
non-Six Sigma companies, these costs are often extremely high. Companies
operating at three or four sigma typically spend between 25 and 40 percent
of their revenues fixing problems. This is known as the cost of quality,
or more accurately the cost of poor quality. Companies operating at Six
Sigma typically spend less than 5 percent of their revenues fixing problems
(Figure 1). The dollar cost of this gap can be huge. General Electric
estimates that the gap between three or four sigma and Six Sigma was costing
them between $8 billion and $12 billion per year.
Figure
1: Cost of Poor Quality versus Sigma Level

What
is Six Sigma?
Six
Sigma is a rigorous, focused and highly effective implementation
of proven quality principles and techniques. Incorporating elements from
the work of many quality pioneers, Six Sigma aims for virtually error
free business performance. Sigma, s,
is a letter in the Greek alphabet used by statisticians to measure the
variability in any process. A company's performance is measured by the
sigma level of their business processes. Traditionally companies accepted
three or four sigma performance levels as the norm, despite the fact that
these processes created between 6,200 and 67,000 problems per million
opportunities! The Six Sigma standard of 3.4 problems per million opportunities
is a response to the increasing expectations of customers and the increased
complexity of modern products and processes.
If
you're looking for new techniques, don't bother. Six Sigma's magic isn't
in statistical or high-tech razzle-dazzle. Six Sigma relies on tried and
true methods that have been around for decades. In fact, Six Sigma discards
a great deal of the complexity that characterized Total Quality Management
(TQM). By one expert's count, there were over 400 TQM tools and techniques.
Six Sigma takes a handful of proven methods and trains a small cadre of
in-house technical leaders, known as Six Sigma Black Belts, to a high
level of proficiency in the application of these techniques. To be sure,
some of the methods used by Black Belts are highly advanced, including
the use of up-to-date computer technology. But the tools are applied within
a simple performance improvement model known as DMAIC, or Define-Measure-Analyze-Improve-Control.
DMAIC can be described as follows:
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D
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Define the goals
of the improvement activity. At the top level the goals will be
the strategic objectives of the organization, such as a higher ROI
or market share. At the operations level, a goal might be to increase
the throughput of a production department. At the project level
goals might be to reduce the defect level and increase throughput.
Apply data mining methods to identify potential improvement opportunities.
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M
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Measure the existing
system. Establish valid and reliable metrics to help monitor progress
towards the goal(s) defined at the previous step. Begin by determining
the current baseline. Use exploratory and descriptive data analysis
to help you understand the data.
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A
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Analyze the system
to identify ways to eliminate the gap between the current performance
of the system or process and the desired goal. Apply statistical
tools to guide the analysis.
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I
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Improve the system.
Be creative in finding new ways to do things better, cheaper, or
faster. Use project management and other planning and management
tools to implement the new approach. Use statistical methods to
validate the improvement.
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C
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Control the new system.
Institutionalize the improved system by modifying compensation and
incentive systems, policies, procedures, MRP, budgets, operating
instructions and other management systems. You may wish to utilize
systems such as ISO 9000 to assure that documentation is correct.
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Infrastructure
A very
powerful feature of Six Sigma is the creation of an infrastructure to
ensure that performance improvement activities have the necessary resources.
In this author's opinion, failure to provide this infrastructure is the
#1 reason why 80% of all TQM implementations failed in the past. Six Sigma
makes improvement and change the full-time job of a small but critical
percentage of the organization's personnel. These full time change agents
are the catalyst that institutionalizes change. Figure 2 illustrates the
required human resource commitment required by Six Sigma.
Figure
2: Six Sigma Infrastructure
Leadership
Six
Sigma involves changing major business value streams that cut across organizational
barriers. It is the means by which the organization's strategic goals
are to be achieved. This effort cannot be led by anyone other than the
CEO, who is responsible for the performance of the organization as a whole.
Six Sigma must be implemented from the top-down.
Champions
and Sponsors
Six
Sigma champions are high-level individuals who understand Six Sigma and
are committed to its success. In larger organizations Six Sigma will be
led by a full time, high level champion, such as an Executive Vice-President.
In all organizations, champions also include informal leaders who use
Six Sigma in their day-to-day work and communicate the Six Sigma message
at every opportunity. Sponsors are owners of processes and systems who
help initiate and coordinate Six Sigma improvement activities in their
areas of responsibilities.
Master
Black Belt
This
is the highest level of technical and organizational proficiency.
Master Black Belts provide technical leadership of the Six Sigma
program. Thus, they must
know everything the Black Belts know, as well as understand the mathematical
theory on which the statistical methods are based.
Master Black Belts must be able to assist Black Belts in applying
the methods correctly in unusual situations.
Whenever possible, statistical training should be conducted only
by Master Black Belts. Otherwise the familiar "propagation of error" phenomenon will
occur, i.e., Black Belts pass on errors to green belts, who pass on greater
errors to team members. If
it becomes necessary for Black Belts and Green Belts to provide training,
they should do only so under the guidance of Master Black Belts. For example, Black Belts may be asked to provide assistance
to the Master during class discussions and exercises. Because of the nature of the Master's duties, communications
and teaching skills are as important as technical competence.
Black Belt
Candidates
for Black Belt status are technically oriented individuals held in high
regard by their peers. They should be actively involved in the process of organizational
change and development. Candidates may come from a wide range of disciplines
and need not be formally trained statisticians or engineers.
However, because they are expected to master a wide variety of
technical tools in a relatively short period of time, Black Belt candidates
will probably possess a background including college-level mathematics and the basic
tool of quantitative analysis. Coursework in statistical methods may be considered a strong
plus or even a prerequisite. As part of their training, Black Belts receive
160 hours of classroom instruction, plus one-on-one project coaching from
Master Black Belts or consultants.
Successful
candidates will be comfortable with computers.
At a minimum, they should understand one or more operating systems,
spreadsheets, database managers, presentation programs, and word processors.
As part of their training they will be required to become proficient
in the use of one or more advanced statistical analysis software packages.
Six Sigma Black Belts work to extract actionable knowledge from an organization's
information warehouse. To
ensure access to the needed information, Six Sigma activities should be
closely integrated with the information systems (IS) of the organization.
Obviously, the skills and training of Six Sigma Black Belts must
be enabled by an investment in software and hardware.
It makes no sense to hamstring these experts by saving a few dollars
on computers or software.
Green Belt
Green
Belts are Six Sigma project leaders capable of forming and facilitating
Six Sigma teams and managing Six Sigma projects from concept to completion.
Green Belt training consists of five days of classroom training
and is conducted in conjunction with Six Sigma projects.
Training covers project management, quality management tools, quality
control tools, problem solving, and descriptive data analysis. Six Sigma champions should attend Green Belt training. Usually,
Six Sigma Black Belts help Green Belts define their projects prior to
the training, attend training with their Green Belts, and assist them
with their projects after the training.
Staffing
Levels and Expected Returns
As stated
earlier in this article, the number of full time personnel devoted to
Six Sigma is not large. Mature Six Sigma programs, such as those of Motorola,
General Electric, Johnson & Johnson, AlliedSignal, and others average
about one-percent of their workforce as Black Belts. There is usually
about one Master Black Belts for every ten Black Belts, or about 1 Master
Black Belt per 1,000 employees. A Black Belt will typically complete 5
to 7 projects per year. Project teams are led by Green Belts, who, unlike
Black Belts and Master Black Belts, are not employed full time in the
Six Sigma program. Black Belts are highly prized employees and are often
recruited for key management positions elsewhere in the company. After
Six Sigma has been in place for three or more years, the number of former
Black Belts tends to be about the same as the number of active
Black Belts.
Estimated
savings per project varies from organization to organization.
Reported results average about US$150,000 to US$243,000. Note that
these are not the huge mega-projects pursued by Re-engineering. Yet,
by completing 5 to 7 projects per year per Black Belt, the company will
add in excess of US$1 million per year per Black Belt to its bottom line.
For a company with 1,000 employees the numbers would look something like
this:
Master
Black Belts: 1
Black
Belts: 10
Projects:
= 50 to 70 (5 to 7 per Black Belt)
Estimated
saving: US$9 million to US$14.6 million (US$14,580 per employee)
Do the
math for your organization and see what Six Sigma could do for you. Because
Six Sigma savings impact only non-value added costs, they flow directly
to your company's bottom line.
Implementation
of Six Sigma
After
over two decades of experience with quality improvement, there is now
a solid body of scientific research
regarding the experience of thousands of companies implementing major
programs such as Six Sigma. Researchers have found that successful deployment
of Six Sigma involves focusing on a small number of high-leverage items.
The steps required to successfully implement Six Sigma are well-documented.
1.
Successful performance
improvement must begin with senior leadership. Start by providing senior
leadership with training in the principles and tools they need to prepare
their organization for success. Using their newly acquired knowledge,
senior leaders direct the development of a management infrastructure to
support Six Sigma. Simultaneously, steps are taken to "soft-wire"
the organization and to cultivate an environment for innovation and creativity.
This involves reducing levels of organizational hierarchy, removing procedural
barriers to experimentation and change, and a variety of other changes
designed to make it easier to try new things without fear of reprisal.
2.
Systems are developed for establishing close communication with
customers, employees, and suppliers. This includes developing rigorous
methods of obtaining and evaluating customer, employee and supplier
input. Base line studies are conducted to determine the starting point
and to identify cultural, policy, and procedural obstacles to success.
3.
Training needs are rigorously assessed. Remedial skills education
is provided to assure that adequate levels of literacy and numeracy are
possessed by all employees. Top-to-bottom training is conducted in systems
improvement tools, techniques, and philosophies.
4.
A framework for continuous process improvement is developed, along
with a system of indicators for monitoring progress and success. Six Sigma
metrics focus on the organization's strategic goals, drivers, and key
business processes.
5.
Business processes to be improved are chosen by management, and
by people with intimate process knowledge at all levels of the organization.
Six Sigma projects are conducted to improve business performance linked
to measurable financial results. This requires knowledge of the
organization's constraints.
6.
Six Sigma projects
are conducted by individual employees and teams led by Green Belts and
assisted by Black Belts.
Although
the approach is simple, it is by no means easy. But the results justify
the effort expended. Research has shown that firms that successfully implement
Six Sigma perform better in virtually every business category, including
return on sales, return on investment, employment growth, and share price
increase. When will you be ready to join the Six Sigma revolution?
[i] Jeremy Main, Quality Wars:
The Triumphs and Defeats of American Business, The Free Press,
1994, 173.
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