The 5 x Why Method (The 5 Whys)

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The 5 x Why Method (The 5 Whys)
Ger de Waard, Management Consultant, Netherlands, SIG Leader
The "5 x why" method has been developed by Toyota to perform an iterative Root Cause Analysis of production-related problems. The "5 x why" method is one of the available tools for performing a root-cause analysis. Its simple design and effective output made the 5 x why method also into a popular method used in Kaizen, Lean Production, Six Sigma, Value Stream Analysis, etc.

  • IDENTIFY THE PROBLEM for which the root cause has to be identified.
  • ASK: WHY has this problem arisen? The result is a reply with a new or different problem.
  • KEEP ASKING: WHY? Take the first answer (or problem) and reformulate the question: Where has this issue has arisen? Repeat these steps until you arrive at the core (root-cause) of the issue/problem.
The 5 x Whys can be used for several things:
  • VALIDATING ASSUMPTIONS: It is a simple tool that helps the Belt to unearth an assumption embedded in the process he/she is investigating. Once an assumption is revealed and of course also tested with data, it ensures excellent results.
  • DETERMINING ROOT CAUSES: However 5 x Why is more used in determining the Root Cause(s) of problems
    This technique is most used in the Analyze phase of DMAIC (Define, Measure, Analyze, Improve, Control). The 5 x Whys doesn’t involve a statistical hypothesis and in many cases can be completed without a data collection plan.
  • FINDING NON-VALUE ADD ACTIVITIES: The 5 Whys can also be used as a tool in Value Stream Analysis. Value stream mapping is as we know hard work because it requires looking at a process as if every step is non-value-added and is costing the organization time and resources. The 5 Whys is an easy way to root out as many non-value-added steps as possible.
Often you need to ask 6, 7 and even sometimes 8 x Why to find the real root cause of the problem. Perhaps a better name would be "Multiple Why’s Method".

An excellent example of 5 x Why is the Jefferson Memorial by Juran Institute.

Our Endorsement to the 5 Whys
Ashok Kella, Manager, India, Member
Yes, recently, in a complex issue dissecting in our organisation, unaware of the 5 Whys theory, we solved the issue to rescue and move towards the goal, but we move on and on down to the every outcome with Why. To our surprise and shocks, the root cause arrived at was all together unimagined and irrelevant but a fact. Today the process is flowing flawlessly, lucidly, and uninterruptedly. We endorse 5 x Why.

Better, but not 'root'
David Week, Director, Australia, Member
Five Whys is a great way to get better answers, but I think that’s it's a problem to call the result THE "root" cause—especially for Western-trained managers, who are culturally trained to think one cause -> one effect.
Every effect has multiple causes. For instance, in the Jefferson Memorial they could have asked different questions:
- What is it about our cleaning method that erodes the stone?
- Why do we assume that the bird droppings have to be cleaned so often?
Each pathway up the causal chain would have led to different answers. Similarly, stopping at the lighting answer is completely arbitrary. They could have continued:
- Why do we light the memorial at night?
- Is there another way of lighting that does not attracted midges at all?
- Are there colors of light that repel midges?
- And so forth?

Causality is an infinite web, not a finite chain. Five whys helps explore the web further than just the first why. But remember that the web extends beyond 5 whys, and other lines of questioning are always possible.

Back to Fundamental Thinking
Ivan Kohlinsky, Management Consultant, United Kingdom, Member
Excuse me, but I am asking myself WHY is this method thought of as new, useful and fundamental, as it is. This method along with such methods as PABLA (problem analysis by logic approach), used by the Atomic Energy Authority at Harwell and 'systems thinking/systems approach' etc were the hot methods in the 60s and perhaps earlier. I think that it is great that methods that enhance fundamental thinking and analysis are in favour again. It makes us 'oldies' still feel part of it.

5-W in Combination with Impact Measurement
Schoenborn, Management Consultant, Germany, Member
I agree with @David that 5-W is a good approach for root-cause-analysis, but you should be aware that there could be several causes.
For that reason I combine 5-W always with a Fishbone-diagram and measure the impact of the identified causes to the tackled problem.
The 5-W method is therefore only the starting point and not the end, respectively the result of a proper root-cause-analysis. Though there might be "easy shots" which don't require a thorough measurement, e.g. a Blitz-Kaizen workshop. Here 5-W could do it also alone.

5 Times Why - the Emperor's New Clothes
Wulf-Dieter Krueger, Teacher, Thailand, Member
Watch your children asking this question again and until they are satisfied with the answer.
This method is no rocket science. However, adults in academia might have forgotten about it.
This seems to be the case at VW, where a top-down management style seems to prevail. Back to the roots of learning psychology - it has been around for ages.

Root Cause by Conscious Approach
srinivas, Lecturer, India, Member
A rational approach is certainly a way to get clarity, however could there be other ways also? For example, what if a person has worked on his inner tendencies which conflict on each other and is successful in removal of conflict? Does he need to pose 5whys? Is there a possibility to get to root cause from a person who is clear in consciousness?

5 x WHY’S is not Enough for Me
David Torres, Manager, Mexico, Member
I took an 8D’s course and the homework was to take a real actual client customer complaint, so my team and I started working on it. Even if I had all company resources to try to find the root cause and we started using 5 Why’s for me that was not enough, and we use interviews with line operators and supervisors, I use cctv to evidence what was going on at production lines, and implement the reporter questions what, how, who, when. Then finally we found the root cause of the problem, since then we use cameras to look from desk what is going on in production.

I Prefer the Following Name for this Tool: Why-Why Analysis
Johnny Michael Tan, Management Consultant, Malaysia, Member
I want to share that when my Semiconductor manufacturing site was pursuing Total Productive Maintenance (TPM) we were introduced to this tool by our Japan Institute of Plant Maintenance (JIPM) Consultant.
As the TQ/TPM Head of Department, I pointed out that "5 Whys" had a misleading connotation to it:
- Often times simplistic issues might just need 2 or 3 or 4 Whys to be asked and the answer /root cause has been unearthed.
- On the other hand, more complex / technical problems could often require up to 8 Whys or even more to as much as 12 to 15 Whys before we can put our finger on the 'root cause'.
I thus changed the tool to be labelled as "WHY-WHY ANALYSIS".

Tools According to Problem Complexity
Rodolfo Dionisi, Argentina, Member
Remember that the first step to solve a problem (or to be more precise, to have reasonable chances of success) is to DEFINE THE PROBLEM AND ITS COMPLEXITY. After determining the problem’s complexity, the next step is to SELECT THE RIGHT TOOL.
  • If we are dealing with problems where the cause-effect relationship is relatively linear and obvious, the 5W method will be suitable.
  • If the problem is more complex, obviously we will have to evaluate the use of other more appropriate tools such as DMAIC, RCA (FTA-Proact) or 8D.

Role of Biases in Determining the 5 Whys
srinivas, Lecturer, India, Member
The 5 Whys as a tool is available for long and is available everywhere. Why is it not effective as it should be in developing nations? And even in developed countries it is not effective at all times?Do we need to probe beyond our perceptions of root cause?

1 WHY is Enough Sometimes
Mireille.durin, HR Consultant, Belgium, Member
@Srinivas: There is always a WHY... Why this situation, why this conflict, why this feeling... But if you are clear in consciousness, you will get to the root cause with 1 WHY only instead of 5 or more :-).

5 Why is Excellent Tool to Start and Get Back to the Basics
Pedro Monteiro, Manager, Portugal, Member
5 Whys is one of the best, simple and effective problem solving tools.
Is it not enough?! Yes, sometimes it isn’t, but as a first approach to a problem which you don't know its depth it is excellent.
It’s incredible how such a simple sequence of whys can add so much value to problem solving.
5Whys is used in your everyday life. With your family, friends, at school, etc. And the fact that it is so simple, with no special training needed and "age/profession-free" is what makes it so special.
Use it!

Preparing for Usage of 5 Whys
srinivas, Lecturer, India, Member
Before we use the 5 Whys is it possible and useful to try to reduce any biases by preparing at different levels of human personality?
What if such preparation is simple and takes 20 minutes of time per day?

You Can Use 1 Why or 5 Whys or Multiple Whys
Not all people can solve a particular problem with just one "why".
And not all problems, even how knowledgeable or experienced you think you are, can be solved with just "one" why.
Therefore you have to always look at the solver’s capability to solve, the objectives in solving the problem and the problem’s condition.
Perhaps you took 1 or 2 or 3 or 4 or 5 "whys' to solve the problem and you are satisfied with the outcome and have met your objectives, then that's it. Be happy.
If the solver is not content or satisfied with the outcome after he thought he has solved the problem with the use of 1 or 2 or 3 or 4 more why’s and his objectives have still not been met yet, then he can freely go further using even more why’s or use the "Multiple Why’s Method".
After all, what’s important is that the solver is happy, the objectives are met, and the problem is solved.

Change 5 Why into Why-why Analysis
Ashok Kella, Manager, India, Member
@Johnny Michael Tan: I agree with you that "Five" is symbolic; the introducer has intended to make you ask why again and again till you reach at the root cause. So Why-Why seems to be a more appropriate name.

Back to Fundamental Thinking
Dietmar W. Sokowski, Consultant, United States, Member
@Ivan Kohlinsky: Good point Ivan. Your comment is ever so true. Similarly, the 7-Ws have been around for a long, long time, yet in some articles they are touted as "new". Likewise, "agile" thinking has been practiced for decades, just without all the buzz.

A Tip for this Fundamental Why-Why Technique
Sudheendra G. Mudikeri, Management Consultant, India, Member
No matter how many WHYs are used, this tool has withstood the test of time as an effective one for ROOT CAUSE ANALYSIS.
When I speak about this topic to freshers in the industry, I stress the fact that usually the third or fourth WHY will result in you getting slapped on your face. Consider the following example, the objective of it is to find the root cause of why a person’s name is what it is:
Q. What is your name?
A. John Doe.
Q. WHY? (1)
A(1) My parents chose it over other probables.
Q. WHY? (2)
A. They liked it probably.
Q WHY? (3)
A It was their choice.
Q WHY. (4)
A A****le How do the hell I know why they liked it? And a slap on the face of the person who is trying to do the RCA.
So when using the WHYS be sure to provide adequate reason and background before you start, this will help a long way and prove effective in RCA.

Why? or: What For?
Olaf de Hemmer, Business Consultant, France, Member
I agree with pointing out that 'root cause' is helpful in solving certain problems. Causality is at the heart of the 'cartesian' way of thinking, the basis of scientific reasoning.
But the majority of management issues involve people, who are definitely more driven by goals (future, positive, to be attained) than causes (passed, negative, not to be repeated). So let’s not forget teleology, at the heart of systems thinking?!
The 'why' question allows both answers: 'because...' (cause) and 'in order to...' (goal). We are trained extensively -since we were children- to answer in terms of causes. But aren't the children more interested in understanding the purpose/goals... of things than knowing their cause?
This is why (sic) I by far prefer to ask "What for?" to solve problems: many very efficient methods were developed on pointing out the goals before imagining solutions: Blue Ocean, Business Model Canvas, Customer Perceived Value, Value Analysis, Lean, Shared Value, Business Analysis...

Even a Single 'why' Can Suffice, Without Overtly Asking 'Why'
C.L. Kappagomtula, Professor, Malaysia, Member
Those of you working in production/operations might have come across this situation several times, and resolved the problem 'hitting' at the very 'root' of the problem.
The first Why can be an overt one, and from the answer you get, one will get into either an 'inductive' (creative) or 'deductive' (logical) process, till you reach the very core of the issue and the associated problem.
Thus, wether you call it the PABLA method or 5 (or as many why’s needed) method, the final objective is to reach the genesis of the issue and then to find a 'fix' for it.
Manifestation of a trivial issue as the Root Cause of a severe problem, affecting smooth production runs can be avoided, even at the trivial stage, when one makes a sincere endeavor to avoid the trivial problem in the 'onset' stage itself. This has been my experience at multiple products manufacturing sites in China for nearly 2 decades.

5 Why is not Japanese
Miguel Sacramento, Business Consultant, Brazil, Member
@Wulf-Dieter Krueger: Yes. Every children has a "multiple why device" already built-in.

Find the Most Cost-Effective Solution after 5 Whys
Bevis Qiu, China, Member
Different solutions can be found through different Why questions. I think we might then compare the costs of them in order to arrive at the most efficient solution.

Children Ask Why? Meaning what For?
Olaf de Hemmer, Business Consultant, France, Member
@Wulf-Dieter Krueger: Are chidren not more interested in understanding the meaning / purpose of things (what for?) than their cause (why?)?

5 Why is not Japanese
Miguel Sacramento, Business Consultant, Brazil, Member
@Olaf de Hemmer: Sometimes yes. It depends on each case. For instance, "Why are you prohibiting this?" and "Why did it brake?" questions are made with different purposes: effect (consequence) or cause.

Children Asking Why
Wulf-Dieter Krueger, Teacher, Thailand, Member
Children ask why for the same reason as anybody else in management or in a company: there is a problem at hand, because something is not being understood properly. And they will stop asking, when the problem has been solved. That is sheer learning psychology that applies to any situation in which learning takes place.
However, educational systems see to it that this natural curiosity is subdued. This applies to any educational system in any country. Since nobody wants to look stupid by asking the question 'why?'. So managers and academia have to relearn to ask WHY.

5 WHY Methodology is Advanced
FASESIN David, Manager, Nigeria, Member
The 5 WHY methodology for problem solving is more advanced than the perspectives of some others discussing it. Conducting 5 Why to solve problems in an organisation requires a multidisciplinary team with members being professionals at various facets of operations vis-a-vis engineering, quality assurance and production departments, among others.
The group will conduct the 5 Whys and this should be done at the GEMBA. Gemba means the site where the problem is identified. Going to GEMBA now refers to carry out "GSTD" meaning Go-See-Think-Do.
At the GEMBA, different questions will come up from the multidisciplinary team members, looking at the issue at hand from the angle of individual member’s discipline aiming at identifying the effect of their resolutions on the product, ultimately, as it would be acceptable and preferred by the consumers, which is the priority in the hierarchy of satisfactory school of thought.
After solving the problem, OPL is required meaning "One Point Lesson" from the issue resolved.

Advanced 5 WHY Methodology
Ashok Kella, Manager, India, Member
@FASESIN David: The effectiveness of Why-Why has been evaluated in combination with GEMBA, GSTD and OPL along with multidisciplinary team involvement.
We have been discussing its effectiveness in its principal position. In combination with other tools the effectiveness is judged in totality. Even if more than one tool is applied, the lead tool is if Why why.

Organisation Service or Product Delivery - Human Analogy-Root Cause
srinivas, Lecturer, India, Member
When we considering an organization as a living being, then there is always a relation to the mind, irrespective of the problem that a particular organ is experiencing.
For example, an organization’s communication system can be considered a mouth organ. If there is problem with the communication system then it has relation to the organization’s mind functions, for example planning, organizing etc.
Since these interdependent relations exist, the root cause can be traced to the thought level. Conflict at thought level is the problem and since consciousness is the base on which thoughts are bubbled then is a solution at conscious level to get rid of a conflict a way out? For example respecting the aspects like sleep, hunger, reflection, intellect etc. in self and others involved in decision making.
Why-Why stresses the intellect part… But by considering all 22 aspects, do we get to root cause? .

Ask as Many Whys as Necessary
jorge anibal hoyos hoyos, Manager, Colombia, Member
When talking about WHYS I also recall my kids when they were young asking all the time "WHY PA?" I think there is no mandatory quantity of WHYS; one should just ask as many WHYS as necessary. That must be the norm to be followed.

Conscious Approach
srinivas, Lecturer, India, Member
We have expert systems which are currently under development which use artificial intelligence and feedback loop mechanisms. To me they will be capable of finding the root cause quickly and accurately, however complex the system may be, by posing an N number of Whys.
However they are not sensitive to aspects such as sleep, thirst, hunger, reflection etc. Software agents using algorithms are not sensitive to all 22 aspects.
These things could help in finding the root cause because the lack of it in yourself and others involved contributes to defects.

Methods of Iterative Root Cause Analysis
We have a lot of tools available in the past and at present to solve problems. This includes the use of “5 Why’s or “The Multiple why’s”. Perhaps one of them (5 Why’s or the Multiple 5 Why’s) could be the best, simple, effective, most advanced, and as a result be of most interest. This is then the case because:
- The approach fits to solve the problem
- The approach meets your objectives, and
- You are capable to use it.
In fact, there are more methods to perform an Iterative Root Cause Analysis that already exist and more methods that can be developed by anyone, anytime. If we are guided on how to use these methods we are able to try them and conclude whether they are enough or not.
On the other hand, if these methods are not enough because you think they did not or will not solve your problem, meet your objectives, or you’re not capable of using it (even if others considered it best, simple, effective, a more advanced, etc.) then you are free to use other methods or create your own if that meets the 3 things mentioned.

My Important Experience with 5 Whys
Lee, Youngki, Consultant, Korea (South), Member
I engaged a company in a training meeting with employees. They raised a major concern that the current company was facing. It was a challenge of a difficult problem to solve. We used the “5-why methodology” in the course to try to solve the problem. It was found that the technique was a good way. I want to continue to learn various knowledge about this method.

Delegation of All Rationally Viable Methods
srinivas, Lecturer, India, Member
If all rational methods including why why approach which can be automated and performance is better then is it not a better way to realize the human potential by using conscious based approaches?

AI and Causes / Goals
Olaf de Hemmer, Business Consultant, France, Member
@Srinivas: I'd be curious to see how AI gets the answer to "why?": the 'cause' may be possible to find in past data, but how can you trace the goal without asking real people?

Feedback Loop Mechanism
srinivas, Lecturer, India, Member
Using semantic web technologies which are based on artificial intelligence it is possible to interpret what the result means. Using feedback loop mechanism it is possible to go into root cause. Wisdom of the past which is proven to be working under a set of conditions can be used to a new set of conditions which are in current context.
However this type of machine learning and to provide the correct proper/wise course of action is still under development. Using current available technology I think it is possible to encode the wisdom of the past under a set of conditions to be available to the current context by way of closed and open world of reasoning and supplement it by way of collaboration with different entities (people and software agents) involved. Validation from the people side would still be necessary as contemplation, the conscious element is missing in software agents. This is particularly so in cases where axioms are based on transformation efforts (wisdom based on one project and at one location or so but not time and space tested).

Stochastic Approach to Root Cause Analysis May Be the Need of the Day
C.L. Kappagomtula, Professor, Malaysia, Member
I fully concur with Ger De Waard's argument to not restrict to 5 Whys alone. There is no real sanctity in this number of Whys, for the root cause is not a function of a fixed digit number of whys.
May be it is also a better idea to bring in other stochastic terms, such as: What, Why, and How into use to find the root cause for any problem:
- What is the Problem?
- Why has the Problem come?
- How it has been caused?
I feel this could be a pragmatic approach to analyze root cause of any problem.

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Jagdish B Acharya

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