Purpose
This Technique is one of the most effective tools for root cause analysis in the lean management. It will find the root cause of any problem and protect the process from recurring mistakes and failures.
The 5 Why’s method is the part of the Toyota production system. It was developed by Sakichi Toyoda, a Japanese Inventor and industrialist, where the technique became an integral part of every business analysis project. The basis of Toyoda’s scientific research is to ask “Why” five times whenever we find a problem. By repeating “Why” five times, the nature of the problem as well as the solution become clear. One of the key factors for successful implementation of the technique is to take an informed decision. This means that the decision making process should be based on understanding of what is actually happening on the project. The root cause analysis process should include people with practical experience. They can give you the most valuable information regarding any problem that appears in their area of expertise. When applying this technique, you will get to know the essence of the problem and then fix it, and also the source of the problem.
A technique for identifying the exact root cause of the problem to determine the appropriate solution. The idea behind this technique is to stop asking why when you have arrived at the root cause of the problem. This technique is used to get everyone to contribute their ideas that will lead to identify the solution for the problem. The participants who are knowledgeable about the problem domain will be able to generate responses that will aid arriving at the root cause of the problem. As soon as the root cause is identified, recommendation for the solution is drawn up. In coming up with the recommendations, the focus should be placed on the root cause as well as the whole chain of the events that led up the problem. Improvements are communicated with all the stakeholders so the benefits of the solution will be clearly visible and understood.
Some of the articles related to 5 Why techniques are as follows,
- Five Whys - https://www.cms.gov/Medicare/Provider-Enrollment-and-Certification/QAPI/Downloads/FiveWhys.pdf
- 5 Why’s Analysis - https://www.ksre.k-state.edu/agsafe/accidents/Root%20Cause%20Investigation%20Tool_06.01.16.pdf
- Determine the Root Cause: 5 Whys - https://www.isixsigma.com/tools-templates/cause-effect/determine-root-cause-5-whys/
- Guide to Five Whys - http://www.root-cause-analysis.co.uk/images/Green%20RCA%20mini%20guide%20v5%20small.pdf
- 5 Whys Technique - https://www.qualitydigest.com/pdfs/ROOT_CAUSE_Webinar.pdf
- Introduction to 5 Whys - https://apps.aoi.wsu.edu/qms/pdf/mod1w_lecture.pdf
- The 5 Whys - https://www.isixsigma.com/tools-templates/cause-effect/determine-root-cause-5-whys/
- Conducting the 5 Whys Analysis - https://www.thecompassforsbc.org/how-to-guides/how-conduct-root-cause-analysis
- Basics of 5 Whys Analysis Method - https://www.brighthubpm.com/project-planning/57124-overview-of-root-cause-analysis-techniques/
One of the main reason why 5 Whys are so popular as root cause analysis is because of the simplicity of the technique. Whenever an problems occurs, just ask “Why” for 5 times to the people working on it. 5 Whys work on the premise that every problem has a cause behind it but a superficial analysis will only depict the symptoms. A persistent inquiry is required to find the real cause behind the issue so that lasting solutions can be taken and the problem doesn’t resurface. Following are the key steps in the overall process of conducting a 5 whys analysis,
- Gather the relevant team members
- Define the problem statement
- Ask why?
For Example, Lets consider jack is sick with nausea and goes to the doctor while expecting to get medication to treat nausea. However, nausea is just a symptom of the problem and treating it does not mean we treat the real cause of nausea. Investigations by the doctor reveal that he has a stomach ache as well and further diagnosis confirms that jack is actually suffering from the stomach infection. 
Some of the books for 5 Whys technique are,
- 5 Whys: One of the Simplest and Fastest Problem Way | Majed F. Rajeh | https://www.amazon.com/WHYS-SIMPLEST-FASTEST-PROBLEM-SOLVING-PROBLEM-ebook/dp/B08BK8HXR2/ref=sr_1_2?dchild=1&keywords=5+whys+books&qid=1593155350&sr=8-2
- 5 Whys: The Effective Root Cause Analysis | Oliver Roderich | https://www.amazon.com/Whys-Effective-Cause-Analysis-improve-ebook/dp/B0871N3ZYG/ref=sr_1_66?dchild=1&keywords=5+whys+books&qid=1593155483&sr=8-66
