The Six Sigma fishbone diagram seeks to point out any problems with a product and get to the root cause of it. It is also referred to as an Ishikawa diagram and the name fishbone came to be because of how the graph resembles the central bone of a fish. It has branches with each of them symbolizing each root of a problem. This diagram is importantly useful in the analyze stage of the DMIAC Process.

When it comes time for a Six Sigma Project, potential causes of a problem are brainstormed and pointed out. They are graphically analyzed on a cause and effect diagram for easy and fast access. Each of them is carefully analyzed, and the major cause is found and tackled head on. Following each successive step any necessary improvements can be done on the product.

The best way to come up with the best drawing is by first using a Six Sigma Tool called the ‘5 Whys’.  Asking the question “Why?” 5 different times will help find out the causes of the problems, which can then be arranged on the chart. One must first identify the main problem that has compelled him or her to come up with the analyses and make it the head of the fish. Then, identify the causes that you think might be contributing towards the problem. The head, or main problem, may include reduced customers, returned products, and any new negative discoveries about the products.

Because of the different lines of business available, there may be different approaches to deal with various issues. Like in the field of manufacturing, there are the 8 M’s that are used for analysis. The 8 different M’s stand for; the machine used, method, material, man power, measurement, Mother Nature, management and maintenance.

In the service industry, a different approach may be necessary. The best approach involves using the 8 P’s which are as important as the M’s in manufacturing. The Ps are; product (which is the service being offered), price, place, promotion, people (the clients), process, physical evidence, and productivity. These are what many clients look out for in many service providers.  Also within the service industry there may be another useful method of analysis known as the 5 S’s. They are just as useful as the P’s can be. They include surrounding, suppliers, systems, skills, and safety. Remember that communication may also serve a very good purpose.

In order to come up with a fully realizable and effective Six Sigma fishbone diagram, it is imperative that the analyzers ask themselves some very basic questions. The questions are; men operating, machines used, measurement methods, materials used, method of processing, the environment and the way the management was actively involved.

Holding a positive criticism and keeping an open mind is the key to success. When the Six Sigma fishbone diagram is completed, then the weighty issues can be handled first and the rest handled in descending order. The choice mostly depends on what percentage of the customers it actually affects. Some of the most common solutions that may be arrived at include improving product quality, advertising the product more, and offering incentives like offers including buy one get one promotions.