The 5 WHY – A Simple Process to Understand any Problem (Root cause analysis)

It is often thought that a concept such as LEAN needs either extensive studies or training to be any good at it. So we leave it to so called consultants to come and teach and train us on lean management and lean principles. While consultants can certainly help with their extensive knowledge and training on the subject, we don’t necessarily have to wait for somebody to teach us on the basic principles and basic tools of lean to start benefiting from it.
The purpose of this article and few more to follow over the next few weeks are to remind you that, as a manager/ supervisor you already know most of the lean tools and how to use them. One of such tool is called 5 WHYS.

5 WHYS is one the easiest and fundamentally most important tool we use in Lean Management. It is often the case that when we do things, things go wrong. It’s normal and if things don’t go wrong there is something not normal with that setup. When things go wrong it is the duty of the supervisor/ manager to resolve the issue and set things right as quickly as possible. However, it is equally important to understand why the mistake or bottleneck happened and take necessary measures to eliminate or drastically reduce the recurrence of the same issue again. In management studies & in LEAN we called this procedure ROOT CAUSE ANALYSIS. Sounds bit fancy but it is nothing but digging in to the issue and try to understand why it happened. 

So what is 5WHY. It is simply asking WHY, WHY, WHY, WHY, WHY and chances are when you are in your fifth why, you should be beginning to understand WHY things went wrong. But in any means 5 WHYS don’t limit your questioning of whys to just 5 times, though often 5 times is enough to figure out the issue.

It is well noted that most problems have several layers attached on top of each other. During the 5WHY route cause analysis you’re simply peeling away each layer to get in to the core of the issue which we called fundamental cause for the problem or trigger point. Without getting to the core issue, it is practically impossible to eliminate the issue or guarantee that it won’t happen again. Sometimes we may find we do not have an answer to the issue but at least now we know what’s causing it so we could keep sufficient allowances to compensate the delays or other impact to the operation.

5 WHY Process

Depending on the nature of the problem you can do this 5 WHY analysis in a formal way or informal way. The formal way to do the analysis is as follows,

1. Gather the team to a one place
2. Identify the problem and write a problem statement
3. Ask the first WHY the problem happened and write down the answer
4. Ask the second WHY and write down the answer. Now relate the answer to the first why and see any relation or correlations there 
5. Repeat the same until team agrees on the core issue to the identified problem in the problem statement. 

5 why process flow chart / image source: buffer.com

Example#1: 

Let’s take an example to see how 5 WHY can be used in a practical situation. Absenteeism is one of the biggest problems in the apparel industry. This causes many headaches not only to factory manager in the manufacturing plant but everybody across the supply chain, including the buyer. But unfortunately this is a least explored area in many apparel companies in South Asia. Some companies get around this issue by having number of few ‘jumpers’ who are multi skilled operators who could replace absentees. But this is a costly exercise and most cases not practical as in some factories absenteeism rate is high as 6-8%.

During one of the projects we identified absenteeism is particularly bad in one of the factories and most of the measures HR came up with not working. Some of the measures were taken was to give high monetary bonus for attendance and gifts for the best attendance. Still the issue persists.

So we took few employees along with the HR manager & factory manager and used 5WHY

1. Why were you absent yesterday?
(a) Machine operator -I had to go to a parent teacher meeting of my son’s school
2. Why didn’t you inform the manager?
(a) Machine operator - No point because he always says no as we have urgent shipments. So when we need we just take it.

3. Why you always says NO?
(a) Factory Manager – I am always short of operators and we have an urgent shipment this weekend
4. Why you don’t have a system in place to resolve these issues?
(a) HR Manager – I didn’t know factory manager says NO all the time. Nobody told me that before

At this stage, to highlight the issue we could ask additional question from the management such as ‘don’t you think teacher parent meeting is important and the operator had to attend?’ This is to highlight the importance of the issue and remind them their responsibilities and importance of having a system to obtain leaves with prior approval without refusing every request regardless of the reason.

Also by knowing how many operators going to be absent on a particular day or a week gives the opportunity to the manager to plan ahead with the minimum impact to the production.

So in above example, as result of 5WHY route cause analysis company identified the fundamental HR management issue they had for a long time and caused so many disruptions to their operations. After the analysis their absenteeism went down to 3-4% within a month which was a huge improvement.

Example#2: 

Let’s look at another common occurrence in a manufacturing floor. Daily production target supposed to be 1000 pieces. However, actual output is 890 pieces. Let’s do a route cause analysis to diagnose the issue.

1. Why the daily target not achieved?
(a) Line supervisor – We ran out of thread & we had to rewind the thread to get the number of cones needed. Specially for 5 thread overlock machines.
2. Why did we ran out of thread?
(a) Production Manager - It seems thread consumption was taken wrong.

3. Why we got wrong consumption?
(a) Merchandiser – I measured the thread consumption manually. I thought I got it right. It seems there was a mistake somewhere. Sorry

As a result of above route cause analysis, management realize the importance of having a standardize system to calculate thread consumption and making sure merchandiser reconfirm the accuracy of consumption with the relevant line supervisor on first day of the production. This will help to order shortage or stop ordering additional qty for future deliveries.

Lets discuss another LEAN tool next week.

About the Author: Charm Rammandala is the founder & CEO of IStrategy USA. He counts over two decades in the fashion supply chain in diverse roles as Lean Manager and Model himself. He is an expert in rolling out programs in Lean apparel manufacturing and Sustainable labour costing. His former positions included being the first Lean Technologist at George Sourcing Services UK Ltd.