Root Cause analysis is a technique used to assess the symptoms of a problem and find the ultimate cause. Finding the root cause is the first step in solving a problem. The fishbone diagram is one visual technique; another technique for root cause analysis is the five whys.
Root Cause also known as “Fishbone Diagram”
The fishbone is widely recognized as one of the standard quality tools. Ishikawa was a pioneer with his approach. A fishbone starts with just one, single problem which doesn’t reflect the nature of real world issues. It reads right to left because the Japanese language reads that direction. It mixes causes and possible causes without specifying evidence. And, it breaks apart the fundamental cause-and-effect relationships within an issue by grouping the causes into general categories.
The five Whys
The why question is one of the most valuable tools and it is used to help dig down to the root cause or underlying reason for a problem or opportunity. The five whys technique recommends that the analyst ask why in response to reason five times to get to the root reason
Example of five Why’s
Problem: Convert the customer database from the ABC DBMS to the XYZ DBMS.
| Question | Answer | |
| Why #1 | Why do you think the organization is funding this project? | The XYZ DBMS is a more current technology. |
| Why #2 | Why do we want to be using a more current technology? | Because we want our systems to be state-of-the-art. |
| Why #3 | Why do we want our system to be state-of-the-art? | Because we don’t want customer or outside competitors to think that we are using old technology. |
| Why #4 | Why don’t we want customer or outside competitors to think that we are using old technology? | Because we want to be perceived as being the leading edge of technology. |
| Why #5 | Why do we want to be perceived as being on the leading edge of technology? | Because if we are perceived as having leading-edge technology, our customers will buy more products from us. |
