Albert Einstein said “Intellectuals solve problems, genius prevent them”
Six Sigma (6σ) is a set of tools and techniques for improving process. A process is said to be a Six Sigma process if it produces not more than 3.4 defects per million opportunities, i.e., 99.99966% of all opportunities to make error are free of defects.
Six Sigma concept is a set of techniques and management tools that have been designed to improve the quality of the output by reducing the likelihood of error. It is an approach that is based on data. It uses statistical methodology for eliminating errors/defects. Six Sigma tools and techniques improve the output quality of a process by the identification and removal of causes of defects and thereby minimizing the impact variability in business processes. It makes use of a set of quality management and statistical methods and creates a task force of people within the company who are well versed with these methods. A defined sequence of steps is followed by every Six Sigma project. Each Project has a specific target like cost reduction, cycle time reduction, increase in profit and improvement in customer satisfaction.
The etymology is based on the Greek character “σ”, a statistical term for measuring deviation from the mean. “Six Sigma” originates from the bell curves used in statistics wherein one Sigma marks a single standard deviation from the mean. If the process is at Six Sigma level, the error/defect rate is classified as very low.
How Six Sigma Process Started?
Carl Fredrich Gauss, a German mathematician and physicist, developed the bell curve in nineteenth century. The bell curve became a very handy tool for finding errors and defects in a process by creating the concept of “normal distribution”.
Walter Shewhart, an American physicist and statistician, elaborated this idea and confirmed that sigma imply where a process needs improvement.
In the late 1980s, one of the pioneers of modern Six Sigma process, Motorola Engineer Bill Smith, created many methodologies that are still associated with Six Sigma concept. The system is influenced by Total Quality Management (TQM) and Zero Defects.
Principles of Six Sigma Concept
There are five key principles of Six Sigma Concept:
Six Sigma Process Steps
The Six Sigma process is abbreviated as “DMAIC”. Each letter in “DMAIC” indicates a phase. Following are the phases associated with DMAIC.
- D: Define
- M: Measure
- A: Analyze
- I: Improve
- C: Control
Details of different phases of DMAIC are as below.
Phase 1: Define
The letter “D” in DMAIC stands for Define, i.e. the first phase is “Define” phase. The objective of Define phase is to define the problem statement. Planning the improvement initiative is also part of Define phase. To define a problem we need to understand current status and the future stage where we want to reach. This phase defines the problem and the target of the improvement plan. The most important goals are obtained keeping customer in mind. The Voice of the Customer is a very important input for identifying the aspects of the process that need to be resolved. The problem statement must include the issues/problems faced by the customer and time period for which the issue has existed. The goals should be SMART, that is, specific, measurable, attainable, realistic and timely. The scope of the project is also defined at Define phase. It is important to correctly identify the activities and processes that are within the scope of the project so that we can identify those situations wherein we try to solve a problem that is not within the scope of the project. In Define phase of DMAIC, the following question is answered ‘What is important for the business?’
Phase 2: Measure
The letter “M” in DMAIC stands for Measure, i.e. the second phase is “Measure” phase. The objective of this phase is collecting the data from the process and assessing the current quality level. During this phase, team identifies the data that is available and also the source of the data is identified. It should be determined that how data needs to be collected for getting the reliable results. If the collected data is unreliable then it will defeat the purpose of Six Sigma process because it is a data-driven approach. A plan to gather the data is developed and data is collected. In the Measure phase of DMAIC, the following question is answered ‘How organization is doing with the current process?’
Phase 3: Analyze
The letter “A” in DMAIC stands for Analyze, i.e. third phase is “Analyze” phase. The objective of this phase is to understand the root cause of the problem by studying the processes and the generated data. In this phase, the processes are analyzed for identifying the different methods to reduce the gap between the current stage and the desired goal. During this phase, the statistical data analysis techniques are used to find out the actual root cause of the problem. It is important that team working on this project is familiar with the statistical analysis tools. In the Analyze phase of DMAIC, the following question is answered ‘What are the issues with the current process?’
Phase 4: Improve
The letter “I” in DMAIC stands for Improve, i.e. fourth phase is “Improve” phase. The objective of this phase is to find out actions for improvement, prioritizing the action plans, testing the improvement, and finalizing the improvement action plan. This phase is all about suggesting and finalizing a solution to improve the process. This is the stage wherein creativity comes into the picture. Team should be able to find new methods to do things accurately at a faster speed with less cost involved in it. Based on the identification of root causes, an improvement plan is put in place to improve the processes and address the root causes of the problems. In the Improve phase of DMAIC, the following questions is answered ‘What changes need to be done to improve the process?’
Phase 5: Control
The letter “C” in DMAIC stands for Control, i.e. the last phase is “Control” phase. This objective of this phase is to ensure the implementation of the improvement plan and put in place controls to monitor the system so that improvements are sustained. In this phase, solutions are implemented and process owner is made accountable for the new improved process. A control plan is put in place to monitor the performance. Statistical tools are used to monitor the performance and stability of the improved process. In the Control phase of DMAIC, the following questions is answered ‘How to track the performance of the improved process?’
Other Six Sigma Process Tools
Following are the management tools used as a part of Six Sigma Concept:
Five Why Analysis
The “5 Why Analysis” technique is a simple and effective technique for finding out the actual root cause of the problem. This technique uses five questions to find out the root cause of the problem. The first step is to state the problem. For example, grammatical mistakes in the paper edited by editor. The second step is to ask keep on asking the question “Why” and breaking down the issue to its actual root cause. In this case there might be two reason. (1) Editor was not clear on grammatical concepts. (2) He did not pay enough time to read the paper.
A Critical to Quality Tree (CTQ Tree) is a Six Sigma tool that is used to identify the requirements of the customer and translate the customers’ requirements into the process requirements. It provides a fair chance to organizations to understand the characteristics of a service or product that are critical to quality. Before starting any process improvement project, it is essential for an organization to determine the characteristics of the service or product that are critical to quality as indicated by customers.
Following are the three components of a CTQ tree
Need: Are we fulfilling customer’s needs with our product or service?
Drivers: While judging quality of product or service, which elements or characteristics will most likely be considered by our customers?
Requirements: Which process is required or what are the product requirements needed to ensure that drivers meet customer standards?
Root cause analysis (RCA)
It is a process by which an organization tries to identify the actual cause of a problem/defect and correct it accordingly, rather than correcting the obvious or surface symptoms.
One thing is common in all the Six Sigma tools and methodologies: they all help streamline processes to give the best products with minimum number of defects.
Lean Six Sigma
Lean Six Sigma is a data-driven and fact-based improvement philosophy that prefers defect prevention to defect detection. It improves the customer satisfaction and net profit by reducing the cycle time, waste and variation by promoting the use of standardized workflow. Hence, it creates a competitive advantage. It is applicable wherever waste and variation exist. Every employee should be involved in this. Six Sigma concept focuses on minimizing the process variation and improving process control whereas Lean Six Sigma concept focuses on eliminating the waste (non-value adding activities) and helps standardizing workflows. KAIZEN is a tool for continuous improvement of the process.
Please refer the following article for KAIZEN concepts:
Difference between Lean and Six Sigma Concepts
The objective of both Lean and Six Sigma concepts is to provide customers the best quality and fast delivery at minimum cost. Although, there is a great deal of similarity between the two; however, they both approach their common goal from slightly different angles:
• Lean focuses on waste reduction while Six Sigma process focuses on variation reduction.
• Lean achieves its targets by using tools such as kaizen, workplace organization, and visual controls, i.e. tool s that are less technical. However, Six Sigma process uses the statistical data analysis, hypothesis testing and design of experiments.
Generally, the successful implementations start with lean approach, reducing waste, using the value stream mapping to improve the understanding and output and making the workplace as effective and as efficient as possible.
Are You Ready for Six Sigma Process Implementation?
Recently multiple enterprises have impetuously used the Six Sigma concept expecting phenomenal success like GE, Motorola, and AlliedSignal. Implementation of Six Sigma concept might seem to be a lucrative plan for many but there are challenges and pre-requisites in implementing Six Sigma concept. Six Sigma process cannot deliver the desired results for your organization if the required factors are not in place.
Hence, before implementing Six Sigma concept, it is helpful to assess if your organization is ready for advanced quality management process. Please find below a few crucial factors that decide your company’s readiness for implementing Six Sigma concept:
- Business Aptitude
Six Sigma process and tools will definitely work for your company. The success ratio is determined by the speed with which the process is absorbed and understood by an organization. The Six Sigma process was first adapted by manufacturing firms followed by other industries. Manufacturing companies with their past quality practices like Total Quality Management, Mathematical modelling and Statistical Process Control have been able to implement Six Sigma concept seamlessly. Similarly, the multiple service-based companies have also adapted the process. Thus, the successful implementation of Six Sigma process depends on the business aptitude of a company.
- Availability of Dedicated Resources
If an organization wants Six Sigma process to work for it then management should ensure that qualified professionals take charge of projects and mentors others working toward process improvement. Though this is obvious but still there are organizations that are trying to implement Six Sigma on a “part-time” basis. This means that company management is trying to utilize the existing resources as “Black Belts”. Hence, if an employee of a company is responsible for an operational job and plays the role of Black Belt a well then the concerned employee will not be able to justify role of Black Belt and Six Sigma process will not lead to the desired results. With two different responsibilities, employee is most likely to focus on regular activities rather than the process improvement projects. This means, Six Sigma concept will not yield the desired result until a company does not have dedicated resources for process improvement projects.
- Top–Down Support
One of the most important factor for successful implementation of Six Sigma concept is the company culture. If Six Sigma or any other process improvement methodology is an unfamiliar concept for the company then organization might face internal resistance while implementing it. Although people naturally resist changes, implementing a new process is possible only by changing the mindset of the employees, right from the top. The company culture is influenced by its leader. If the top management does not believe and commit itself to Six Sigma, the rest of the employees will never believe in Six Sigma concept. Six Sigma process or any other initiative is unlikely to be successful in an organization if it turns out to be a grassroots campaign.
It is always the case that a few employees in the organization do not accept the new initiative and never get convinced. However, the support from the top management will definitely institutionalize the initiative as a requirement of the business. Jack Welch, GE former chief executive officer, initially received resistance from managers when Six Sigma process was implemented in 1996. When GE managers assumed that Six Sigma process was a short time activity, Welch informed employees that promotion to senior management positions would depend on Green Belt of Black Belt training. Managers soon realized that Welch was quite serious and Six Sigma was not a short-term policy.
- Incentive for Employees
Assuming that organization’s leadership provides necessary support, there must be motivation for rest of the employees to accept and implement the new initiative. Be it a financial incentive or it is linked to each employee’s performance assessment or advancement, a system must be put in place to ensure that employees get motivated and remain engaged. This is simply linked to company’s commitment to Six Sigma. Management should not expect that a new initiative thrown at their staff will be readily adopted by employees. Six Sigma can be a fundamental change in approach for many companies. Overcoming resistance and changing the mindset of employees is never an easy task. It may be debatable that which methodology is best but if top management does not employ a strategy then employees will not quickly embrace the new ideas.
- Training Programs
Training is a mandatory part of Six Sigma deployment. Following aspects of training plan should be kept in mind: (a) what are the training objectives? (b) Who all will be covered in training and what will be the order? (c) Will there be same training for everyone? (d) What will be the training structured and which areas will receive more attention? (e) What will be duration of the training program? These questions should be kept in mind while evaluating training plan. The details related to six Sigma Green Belt certification can be found here.
- Alignment with the Project
Once the Six Sigma gets started and employees are trained, multiple ideas for projects get generated. It is not important that how many projects get launched, their impact on the bottom-line is important. At times, several completed projects have unending work in progress. Increasing the number of the Black Belt and Green Belt projects might primarily help culture change within the company, if the company can take care of the following two pitfalls:
- When employees become part of multiple projects they can find it difficult to manage time. This can lead to Six Sigma overload and can result in the unsatisfied project deliverables
- When the projects are started without any key-stakeholder assistance or without top management involvement, it can negatively impact the project
Hence, before launching Six Sigma it is important to evaluate on how the projects gets chosen. It is essential to link the projects with key business indicators and metrics. Projects that appear to be the “Feel good projects” will generally result in eroding Six Sigma as such projects do not add any value to an organization.
- Effective Communication
Companies must have accurate internal communication process so that that information related to Six Sigma projects is conveyed down the line effectively. When an organization maintains an effective internal communication process it helps promoting Six Sigma concepts and also speed up improvements. It also helps sharing the best practices.
Six Sigma is an approach for improving the business performance. Six Sigma uses the statistical analysis rather than guessing to find out why a particular process is not yielding desired results. The process is improved and measures are put in place to ensure process becomes stable. The end result is an improvement in the bottom line.
The objective of both Lean and Six Sigma is to provide customers the best quality and fast delivery at minimum cost. Although, there is a great deal of similarity between the two; however, they both approach their common goal from slightly different angles: (a) Lean focuses on waste reduction while Six Sigma focuses on variation reduction. (b) Lean achieves its targets by using tools such as kaizen, workplace organization, and visual controls, i.e. tool s that are less technical. However, Six Sigma uses the statistical data analysis, hypothesis testing and design of experiments.
DMAIC is a data-driven improvement approach that is used for improving and optimizing the business processes. It stands for Define-Measure-Analyze-Improve-Control. DMAIC is the core tool used to drive Six Sigma projects.
The “5 Why Analysis” technique is a simple and effective technique for finding out the actual root cause of the problem. This technique uses five questions to find out the root cause of the problem.
A Critical to Quality Tree (CTQ Tree) is a Six Sigma tool that is used to identify the customer’s requirements and translate the requirements into the process requirements. It provides a fair chance to organizations to understand the characteristics of a service or product that are critical to quality.