The Six Sigma methodology is a process improvement approach that is designed to improve employee productivity, process efficiency, and business outcomes by reducing defects and variation.
It was originally developed in manufacturing at Motorola, by the engineer Bill Smith. Over the years, however, the methodology has delivered excellent results for many businesses around the world.
It has since spread, not only to a number of business disciplines, but also to a large number of organizations and industries. Many, in fact, have adopted it formally as their primary means of quality control and business process improvement. Below, we will look in more detail at this methodology, its benefits, its drawbacks, and its alternatives.
What Is the Six Sigma Methodology?
Six Sigma is a term that originated in statistical quality control. It refers to a process wherein 99.99966% of opportunities to produce a part’s feature are free of defects.
The goal of the Six Sigma methodology is therefore to reduce the number of defects in a process by minimizing variability in a process.
For many, the statistics behind this method are less relevant than the outcomes produced by this methodology.
Overall, Six Sigma aims to accomplish goals such as:
- Reducing variation and increasing predictability
- Minimizing defects in products and increasing process efficiency
- Improving quality of products, customer experiences, and customer value
- Improving the organization’s financials
Like many business process improvement methodologies, Six Sigma can be implemented across the organization. That is, it can not only be applied at the frontline, but also at the strategic level, in management, and everywhere in between.
Core Tools in the Six Sigma Methodology
Generally, Six Sigma is a data-driven methodology that relies heavily on statistical, scientific methods.
Among the easier tools to understand, however, are two frameworks: DMAIC and DMADV.
DMAIC is a framework intended to improve existing business processes and stands for:
- Define the system, the customer voice, project goals, and other relevant requirements
- Measure the process and collect key data
- Analyze data and determine cause and effect
- Improve the current process using data-driven methods
- Control the process and minimize variations to avoid defects
DMADV is a five-step process intended to launch new projects or processes, and it stands for:
- Define design goals that align with the organization and the customer’s needs
- Measure characteristics that are critical to quality, product capability, risks, and other relevant data points
- Analyze and create alternative designs
- Design an alternative based on the information collected from the previous step
- Verify the design, test it, implement it, and transfer ownership to new managers
These are five-phase, repeatable frameworks, which can be applied continuously across manufacturing, management, and other business processes in order to accomplish Six Sigma’s main goals of quality control and improvement.
What Are the Pros and Cons of Six Sigma?
There are several reducing errors variation and defects within business processes accomplishes several goals, such as:
- Improving organizational effectiveness
- Increasing process efficiency
- Reducing costly errors and mistakes
- Improving business output and outcomes
Ultimately, as mentioned, the one of the primary aims is to improve the organization’s financials and profitability by increasing the quality of products and enhancing customer value.
Clearly, there are several reasons why Six Sigma has become so popular, and the outcomes of many companies demonstrate its value. Honeywell, General Electric, and many other Fortune 500 organizations had adopted the approach. As a result of these initiatives, many organizations saw marked reductions in costs and improvements in quality.
That being said, although Six Sigma has produced major benefits for many who use it. It is not free of downsides.
Some criticisms include:
- Its lack of originality
- The poor quality of Six Sigma certification programs
- Over-reliance on statistics
- A lack of creativity
- A limited focus on process improvement, rather than innovation and growth
This limited scope means that Six Sigma may exclude other important areas of the business, so it should not be viewed as a “cure-all” to an organization’s problems.
Six Sigma In Practice
Clearly, Six Sigma can generate positive results for an organization, but, since it is limited in scope, it should not be applied universally to any business, process, or discipline.
Instead, it should be used with the intention of improving efficiency, reducing errors, and optimizing processes.
As we saw, an organization that relies too heavily on Six Sigma may lose sight of key business functions such as innovation and growth.
To minimize these risks:
- Six Sigma should be applied to appropriate business initiatives, such as product development and manufacturing
- Other process improvement methodologies, can augment Six Sigma and address areas that Six Sigma does not
- Six Sigma can also be combined with certain methods, such as lean, to create hybrid methodologies that are more flexible and relevant to a specific organization
- Businesses should adopt other business principles, such as those that prioritize innovation or agility, to accomplish goals not addressed by process improvement methods
In short, Six Sigma can generate significant performance gains for an organization, but this methodology is limited in scope. Its implementation should therefore be restricted to the optimization of specific types of processes, and different frameworks should be applied to enhance other areas of the business.