The Significance Of Six Sigma

Published Date: 02 Nov 2017

Six sigma according to financial times ‘‘is a program aimed at the near elimination of defects from every product, process and transaction." It is mainly a tested and verified method that assists organisation and business to be run more efficiently and profitably (Brue, 2005) .The Greek alphabet sigma is a statistical term used to measure process variations on how a given process that is causing defect deviates from excellence,. Six Sigma works in a way that manage variation and eliminate defects--or rather get them as close to zero as possible (Harrison, 2006)

Therefore a six sigma practice is one that delivers a fault rate of less than 3.4 parts per million even when the mean itself shift by up to 1.5 sigma in either positive or the negative direction. In other word the company should operate at 99.997% precision (Stevenson and Mergen 2006). The distribution curve shown below in figure 1 demonstrates the terms variation and mean used.

Six sigma is a management philosophy developed by Motorola to originally focused on improving the quality of manufactured component later expanded for improving any business process However over the past two decades Six Sigma has evolved from a focus on metric to the Methodology level and finally to the design and development of entire Management Systems. As a Metric, when a process is operating at Six Sigma level, it will produce nonconformance (i.e., defects or errors) at a rate of not more than 3.4 defects per one million opportunities.

As a Methodology, Six Sigma leads to business process improvement by focusing on understanding and managing customer expectations and requirements (Brewer and Eighme, 2005; Rudisill and Clary, 2004). As a Management System, Six Sigma is used to ensure that critical improvement opportunity efforts developed through the Metrics and Methodology levels are aligned with the firm’s business strategy. Therefore there are two different methods that are generally used in Six Sigma methodology They are 

DMAIC Methodology

DMADV Methodology

DMAIC Methodology is mainly used in already existing processes or product that is underperforming. While the DMADV Methodology can be used in two ways. It is used when organisation is trying to develop a new product or a process, or can also be used when an existing product or process that is already existing but does not meet the six sigma level of customer requirement. The DMAIC methodology has a five stage process that include Define, Measure, Analyze, Improve and Control, while in DMADV Methodology the initial three stages are the same as those in the DMAIC methodology and the last two stages are Design and Verify.

The significance of six sigma

In general Six Sigma is a quality improvement methodology that was first started by Motorola when they realised that they were losing business and productivity through the cost of non-quality . When Motorola implemented six sigma the quality of their product had improved, but what originally started as improving the quality of manufactured components has later expanded for improving any business process, an example is Drug wholesale McKesson which have use six sigma to improve a variety of supply chain processes, such as inbound trailer cycle times and pick face replenishment efficiency.

The argument is that sigma philosophy is not just a quality control tool that aims at defect free product, but it’s also a customer centric process that focus at customer satisfaction hence delivering customer requirement and so the heart of all improvement action is built on customer requirement and needs.

Since the fundamental of Six Sigma is the removal of waste of all kind resulting in the best use of all resources in an organization, if implemented fully it will results in, higher customer focus, enhanced customer satisfaction, reduced costs and a better profit ,hence increase market share by giving a competitive edge over other competitors. (Sagey, 2007).

however while there are many reward for implementing six sigma there are few challenges that needs to be overcome. First the cost of implementing six sigma is expensive, it also needs 100% commitment from the employees who are a part of the project, and finally other than concentrating on other days to day’s activities it required a lot of time is spend on and dedicated on the project

Roles and Responsibilities.

In six sigma the project are run by people who are well trained in the philosophy and its application and they are mainly determined to eliminating defect whenever they are in the business process and therefore have different roles and responsibility.

Black belts are employees who have been trained in the philosophy and its application whose effort is to focused on discovering defects on business process and eliminating it, he or she moves from department to department to helps in the team build up and to create confidence while keeps the project going to achieve the desired result.

Black belts are normally backed up by project champions who are in the senior management level to help overcome the challenges and obstacle throughout the six sigma project,. A black belt normally can do up to four projects a year.

Master Black belts (MBB) in most of the companies are people who coach and mentor the black belts who work on a variety of project. Their main responsibilities are to ensure that the black belt and his or her team stay on track and complete their work. Master black belt are normally most highly train and skilled expert they may occasionally designates an external consultant specialist in Six Sigma process improvements.

The Green Belt is mainly involved with six sigma project as the role of assisting or as a part time, they help in collecting the data for the black belt team leader, also they have a job with normal duties and serves lower level management leaving the harder task for black belts. (Pande & Holpp, 2001).

Six sigma Implementation

Implementing six sigma is not an easy task and does not necessarily translate into instant results, and therefore Implementing six sigma involves a five step process also called DIMAC/DIMADV (define, identify, measure, analyse , control design and verify)

In the first stage, the company leader defines the problem or an opportunity within a particular process, identified the sponsor as well as setting the project goals by identifying the customer requirement and lastly forming the team timeline for the project set

In the second stage all the variables that impact a particular process are identified and defect level reduce and evaluated and track while monitoring the process performance and use the result to determine the stability, process capability, reproducibility and repeatability.

In the third stage the practitioners of the six sigma use a variety of statistical tools to try and find the relationship between the various variables that constitute the inputs and outputs of a process. They establish the hypothesis or the questions describing the problem. Also decide on the suitable techniques to prove the hypothesis. Finally they analyze the results and reach conclusions and then validate the process.

In the fourth teams brainstorm to come up with the solutions to remove the root causes of the service or the product. Teams might have many solutions, so they select the best solution by using various tools like pareto to analysis its , controllability, cabability its safety, and cost effectiveness.

In the last stage that is the Control stage, teams focus on the developing the procedures to maintain the gains that were realized in the previous stage. They also identify the opportunities to reproduce the gains (Sharma, 2003).

In the DMADV the first three steps are the same as those in the DMAIC methodology. The last two stages are Design and Verify. Where the companies design details, optimize the final design and plan for design verification. And in the last stage, the companies verify the design, which may involve setting up pilot runs before turning over to production

However while there are many reward to implement six sigma successful implementation is not easy and does not necessarily translate into instant results, implementing six sigma on less important project, the fact that people are resistant to change and six sigma 100% commitment requirement from employees are possible challenges that may hinder proper and successful implementation of six sigma

Therefore in order to overcome these challenges of implementing six sigma there must be commitment and conviction of leadership support from top to bottom, availability of dedicated resource such as committing personnel to lead and mentor others in the project while focusing on process improvement on day to day basis, employee incentive, proper and essential training and finally commitment to communicate the progress and result of the project as well as the lesson learnt.

Conclusion

In conclusion we have seen that Six Sigma is a powerful tool or method that can reduces and eliminating defects in a process thus increasing the long term viability of a business and is therefore a means of both growth and change.

However simply kicking off a Six Sigma program does not immediately guarantee results but they need to know that successes will takes time, but the chances can be successfully increase by dispassionately by evaluating if the essential factors for success presently exist in the organization

As with any process, Six Sigma also has some disadvantages but the return outweigh the disadvantages and that there is no doubt that regardless of how big or small organisation companies are will benefit from six sigma if implemented well.