Six Sigma Quality

Six Sigma approach to quality and productivity improvement

Six Sigma emerged in the 1990s as a registered trademark and service mark of
Motorola, Inc. as a business process improvement approach searching to find and
eliminate causes of defects and errors, reduce cycle times and cost of operations,
improve productivity, achieve higher asset utilization and better meet customers
expectations. It is based on a simple problem solving approach entitled "DMAIC",
which stands for Define, Measure, Analyze, Improve, and Control, which incorporates
a wide range of statistical and other kinds of quality improvement tools and techniques.
The focus of Six Sigma is on improving four key initiatives: Quality, Productivity,
Cost, and Profitability. Bill Smith, a reliability engineer at Motorola, Inc. is credited
with originating the concept during the mid 1980s. This concept was subsequently
implemented at Motorola, Robert Galvin, CEO. Six Sigma was also
implemented at General Electric Company by its former CEO Jack Welch who made
it a popular approach to quality improvement initiative in mid 1990s. Since then, Six
Sigma has been appealing to many top business executives, as compared to Total Quality
Management (TQM), because of its focus on measurable bottom-line results and its
disciplined fact-based approach to quality problem solving.
The term "Six Sigma" has also been associated with process capability analysis where
product specification and tolerances are compared to the inherent variation in the
process of making the product. Six Sigma approach to process improvement focuses
on reducing the variation in the production process to the point where it will be able
to meet the specification and tolerance requirement of the product, by improving
the process using process statistical tools such as process capability analysis, cause
and effect diagram and Statistical process control. Similarly, Six Sigma approach to
product design focuses on improving the product design to meet or exceed customers'
satisfaction by using methods such as Quality Function Deployment (QFD), Taguchi's
methods of product design, and robust design.
Six Sigma Quality Improvement Model
The Six Sigma quality improvement model as applied by Robert Galvin at Motorola, lnc
refers to the five step process problem solving approach as DMAIC:(Define, Measure,
Analyze, Improve and Control) as explained below:
Define: this step defines who the customers are, what the customers want, the process
capabilities, and provides objectives for project-based improvement efforts.
Measure: this step measures the quality characteristics that reflects improvement in
customer satisfaction and product performance and provides the metrics of data on
which the improvement efforts will be based upon.
Analyze: in this step, data collected in previous steps are analyzed using analytical
tools such as Pareto analysis, process flow diagram, fish-bone diagram, statistical
process control charts, for identifying necessary design and process modifications
for achieving customer satisfaction and performance objectives.
806 International Journal of Management Vol. 24 No. 4 December 2007
Improve: in this step resources are allocated so that design and process modifications
needed for improvement can be implemented.
Control: in this step the process is monitored using quality management tools such
as Pareto charts, and statistical process control charts to ensure that the performance
improvements are maintained.

1. Deming, W. Ed., Fourteen Point Suggestions for Management, 1960.
2. Barney, Matt, (2002), "Motorola's Second Generation" Six Sigma Forum Magazine,
Vol. l,May, p. 13-22.
3. Eckstein, A.L., and Balakrishnan, J. (1993), "The ISO Series :Quality Management
System for the Global Economy." Production and Inventory Management Journal,
Fourth Quarter.
4. Hendricks C. And Kelbaugh R. (1998) "Implementing Six Sigma at GE" The Journal
of Quality and Participation. July/August, p.52-56
5. Treichler,D. et. al (2002), " Design for Six Sigma: 15 lessons learned." Quality
Progress, January, p.38-40
6. Young, Janet (2002) 'Driving performance results at American Express", Six Sigma
Forum Magazine, November, p. 19-27.