Six Sigma is a statistical concept that aims for near perfect production processes. It seeks to reduce defects to 3.4 per million opportunities by focusing on eliminating errors from processes. The chapter introduces Six Sigma and its objectives of driving towards zero defects across all business operations to improve customer satisfaction and reduce costs. It distinguishes Six Sigma from other strategies by focusing on process improvement over outcomes to repeatedly produce high quality results.

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Chapter 1: Overview of Six Sigma
This chapter is an introduction to Six Sigma. It aims to give a basic idea of Six
Sigma, its application, scope and origin. However, Six Sigma is a complex
concept involving principles of statistics and process dynamics. We shall
define Six Sigma only later once you have an understanding of the principles.
Learning Objectives
This module will:
1. Give a basic overview of what Six Sigma is
2. Define the objective of Six Sigma
3. Enable you to see why a company should implement Six Sigma
4. Allow you to differentiate between Six Sigma and the Breakthrough
strategy
5. Give you an insight into the origin of Six Sigma.
What is Six Sigma?
A statistical concept that says that a process is operating so well that it allows for
less than 3.4 defects per million opportunities. The Greek letter σ in statistics
measures the variation of all the outputs in a process.
If a process allows for outputs to be acceptable only if they fall within Six Sigma or
Six standard deviations from the average for all outputs in the process, then you
have a process that is essentially delivering no defective outputs at all.
Six Sigma is a long-term strategy and takes 3 to 5 years to implement. It is
applicable to all types of industries and companies, be they manufacturing or
services.
Objective of Six Sigma
The objective of the `Six Sigma' approach is to move towards zero defect level. It
encompasses all facets of business, such as planning, operations, maintenance,
delivery, and quality, which can lead to customer dissatisfaction.
Six Sigma is based on a foundation of Metrics. These metrices can be organizational
objectives (example On-Time delivery), departmental objectives (such as Cycle-time
reduction) or process objectives (such as Orders processed). It might be worthwhile
linking this concept with ISO 9001-2000, which has a strong inclination for Metrices.

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It creates a better process by eliminating opportunities for defects even before they
can occur. This has a direct impact on the bottom line in terms of:
1. Reduced costs
2. Improved customer service
3. Waste elimination
When we say a process is `Six Sigma', we are saying that it is the best in its class.
Such a level of capability will result in having only something like 3 to 4 non-
conformances in a million opportunities.
Six Sigma – Impact on Cost
Research and studies show that Six Sigma has had a direct impact on Cost of Quality
by directly contributing to all the components of Quality cost.
Why Six Sigma?
In any industry, organization or daily process, when you don’t know what you don’t
know, the hidden costs are huge.
In a Jam manufacturing unit, the nozzle filling up the bottles often fills either excess
or less than the specified quantity. In the former case, jam over flows out of the
bottles thus soiling the bottles as well as the conveyor belt. For bottles that have a
lesser quantity of jam, it is poured manually into the bottles, and in this process too
the result is sticky bottles. To clean the bottles, hot water has to be sprayed to avoid
damaging the bottles that contained hot jam.
Thus we see that a single error often goes unnoticed or is not given much
importance. But when all the possible errors that exist in a system are considered,
the monitory impact on overall productivity, customer satisfaction and profitability
multiplies dramatically.
Six Sigma helps you identify what you don’t know, indicates what you should know,
and helps reduce the errors and rework that cost you time, money, opportunities and
customers.
Why Six Sigma?
Six Sigma’s focus is on the process rather than on the final outcome.
But why should companies focus on the process rather than on the final outcome?
Final outcomes or results are dictated by what happens during the process.

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You may have set an objective; say, develop some new solution in record time. But if
your emphasis was on the final outcome and you did not really keep a check on the
process, then, when you are asked to develop the same software again, you may
well repeat the same mistakes, come across the same problems and all you have is
your memory to fall back on. On the contrary, if the process was documented, you or
anyone else can repeatedly produce the same output again and again. You would
also avoid making the same mistakes. You might even manage to reduce the
development cycle. By focusing on collecting and improving process measures, you
would eventually improve the entire process.
Six Sigma and the Implementation Strategy
A business can improve its profitability dramatically in every sphere by using the Six
Sigma Implementation Strategy.
Six Sigma and the Implementation Strategy are two distinct aspects.
Six Sigma is the philosophy with the goal of reducing the defects frequency to 3.4
defects per million opportunities.
The Implementation Strategy provides the means to achieve that goal through a
highly focused system of problem solving. Implementation Strategy is also called
Breakthrough strategy (term coined by the Six Sigma Academy)
Summary
Six Sigma is a statistical concept whereby a process is it is operating so well that it
allows for less than 3.4 defects per million opportunities.
If a process accepts outputs only if they fall within Six Sigma from the average for all
outputs, then it is essentially delivering no defective outputs at all.
Six Sigma has two major goals; Cost reduction and Total customer satisfaction.
Implementation Strategy provides the means to achieve Six Sigma goal through a
highly focused system of problem solving.