The Six Sigma 5 whys system was designed by a trained and certified six sigma professional to help resolve issues in a quick and easy tool. By asking a series of five ‘why?’ based questions the cause of the problem can be found which will eventually lead to the solution. Since its creation, the system has been adopted by many companies all over the world.

The fish bone diagram is one of the main techniques used in the Six SIgma process.  These diagrams are comprised of  little lines coming off of a main line which show the reason why a particular event happened. The diagram is generally used in the prevention of defects and helps to identify potential factors which will add to the overall effect. When the cause has been determined, it is usually categorized into groups which are used to create the end result.

The groups consist of people, methods, machines, materials, measurements, and the environment. People groups are made up of any individuals involved with the overall process. Methods include how the processes are followed and the items required for making it work such as procedures, rules, regulations, laws and policies.  Machine groups include equipment such as computers, tools, heavy machinery and other items used to complete the project. Materials are made up of parts, paper, pens and other raw materials that allow for the completion of the procedure. Measurements are used to generate data used for evaluating the process. The environment group consists of time, temperature, location and the culture where the procedure is performed.

Tabular format is the secondary technique which is used with this system and is comprised of creating a spreadsheet using Excel. During this process the why questions are added into separate columns aptly named why 1, why 2, why 3, why 4, and why 5. The next column consists of the main root cause identification which is used to create the end solution. The recurrence prevention column is designed to house the end solution that can be referenced if the problem should occur again in the future.

With all the success using this procedure, there are some criticisms as well and these include a list of foreseeable problems. Some reasons for doubt include the tendency of personnel who are investigating the issue to stop at the top level problem without pursuing it further. There is also the inability to go beyond the level of knowledge that the person possess.

Another issue that causes problems during this procedure is the lack of support for the Six Sigma Professionals conducting the study. With a lack of support, the person working on the problem is unable to clarify or receive assistance and will ultimately fail. When multiple people are working on the same problem, they tend to come up with multiple issues for the same problem.

The final issue that can arise with the Six Sigma 5 Why systems involves finding multiple root causes for each question, leading to a longer process which will not resolve the issue. When working with the Six Sigma 5 whys system, it is highly recommended that each answer be verified prior to moving on to the next question in order avoid problems.

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