March 12

Why 5-Why Analysis Is Flawed (& How To Implement it Correctly)


There are a lot of people that preach 5-why thinking. I do too. There are however, flaws in how most people approach it. I thought I’d air my views…

For those that want a quick answer on what 5-whys is, here goes…

What is 5-why analysis? 5 Whys is a simple concept that allows people to delve deeper to understand problems. It simply consists of asking “why” to each answer you uncover. By doing this, you keep digging deeper and exposing additional causes in a cause and effect chain. Eventually, you’ll find the root cause to the problem.

The problem with 5-why is the fact that people take it too literally, and miss the point of what it truly is. I’ll share with you want i mean…

5-Why Analysis – Cause & Effect

5-Why: At its core is one of the most simple continuous improvement tools you’ll find. It’s a tool that can help teams get to grips with a problem pretty quickly.

Like business problem-solving itself, it can be hard. Hard to find what to improve and what to fix.

But the reality in fixing many issues is to look at problems as a group of activities that happen in a chain of events. These chains cause the problem.

Problems and Trees

Let’s say that we have a problem.

  • The machine is broken
  • The customer has complained
  • We couldn’t finish the project on time
  • We didn’t make any profit on the last project
  • The job has to be reworked from start to finish

It’s easy to see these problems, but harder to see why they happened.

Think of them like a tree…

You can see the visible effects above the ground…But you have to dig below the surface to see the roots. And these roots are interconnecting through a chain of cause and effect relationships.

5-why, as with other root cause analysis tools, allows us to dig deeper to expose these cause and effect chains, by asking ‘Why’ over and over again. Each time, we learn a little more about the problem because we are drilling deeper and deeper.

Think Like a Child

If you listen to a young child, they often ask why a lot.

“Why are we going to the shops?”

“Because we need more food.”

“Why do we need more food?”

“Because we’ve eaten it all.”

“Why have we eaten it all?…..”

I’ll stop there before we enter into a science lesson. But you get my point.

This approach seems to happen a lot when children are taking in the world around them. They are gaining as much information and reasoning as they can.

5-why analysis captures this concept – one which we often forget as adults.

We just have to ask ‘why’ to the problems that we encounter. And by asking why each time, we can expose the roots to our tree and understand the problem a whole lot more.

Some Examples of 5-Whys

We know the concept of 5-why analysis is to ask why until you get to the root cause – or what you believe is the root cause.

It’s called 5-why because it was identified that often, most problems can be resolved within around 5 rounds of why questioning.

Here are a couple of 5-why activities to help you see.

Notice the simple wording in each answer. 5 Why needs clear answers, that focus on one specific point

In this 5-why session, it appears that a training process has not been defined to assist teams in knowing exactly what to do and when to archive their paperwork.

Here’s another…

Again, simple and concise answers. Here, there seems a relationship between the despatch process taking too long, which impacts on the amount of work that goes out on time. This comes from poor training and understanding of optimised layout and procedures.

The 5-Why Flaws

Here are my bug-bears to the 5-why questioning approach.

Stuck on 5

A lot of people get stuck on the 5-whys specifically. I’ve heard people say that you must stick to around 5 questions, and then stop. 5 questions is enough!

I’ve even read an article recently that suggested that it should be just 5 questions because that’s what lean is about: to be super quick. Get in and get out. If you ask any more you may uncover more issues which increases the scope of the problem and means you’re spending more time on it.

Hang about – aren’t we there to fix problems?

Shouldn’t we complete as much analysis that’s required to fix the problem for good?

Just by superficially doing 5-why questioning, so you’re not wasting too much time is a fallacy. The problem will certainly rear its ugly head again…all because you’re treating it as a 5-why exercise, rather than a problem solving activity.

I’ve even recently seen a company that created a 5-why template in word that had… yes you’ve guessed it, 5 boxes to answer only 5 whys.

In fact, i have a large library of templates gathered over the years. Each one is restricted to 5 boxes to complete your 5-why analysis.

If you think about it, it’s illogical. What if i need to ask 10 questions to get to the root cause? I’ll stop because the form tells me to? Or it’s “not lean” to carry on?

You’ll find (and i’ve seen it time and again) teams pick and choose which cause-and-effect chain they go down, so they can keep their 5-why analysis simple.

What’s the point in that?

Why Analysis

That’s why I call 5-why analysis, just simply Why Analysis. Don’t get hung up on how many Whys you need to ask. Ask enough to see the problem in it’s entirety – and then fix it for good.

Use this analysis to expose the tree and all its roots. When you do this, something extraordinary happens. You understand the problem like you’ve never seen it before.

You can then create actions that really eradicate the problem, so it doesn’t come back.

Create a Map of Causes

Whilst I acknowledge that a lot of simple problems can be resolved quickly using basic 5-why questioning, the power of it is when you follow it through to the end.

The thing is, it’s often the case that not one event is the root cause. It’s a culmination of causes that come together to create the problem.

In our examples above, and the way that most people practice 5-whys, most people try to follow a certain path in fear of branching out to something else and going “out of scope.”

But here’s what actually happens to problems in the real world:

Beyond 5-why: Cause-and-Effect-Chains
Think of problems as a number of causes that combined, cause the problem

If you mapped the many chains that happen before the problem, you’ll find a number of branches and causes. Some have two or three causes that happen at the same time for the problem to happen.

These are the AND relationships that you wouldn’t find in a simple 5-why questioning approach, and other tools.

The point is, you’ll find a number of causes that contribute to the problem.

What About Fishbone Diagrams?

Fishbone diagrams are a great tool to bring the team together, whilst quickly and effectively brainstorming possible causes.

Yes, they show lots of possible causes.

So too, you can dig deeper to find what I call, sub causes, and those cause and effect chains.

The issue with the Fishbone diagram is that despite being able to allow you to step back and see more than what 5-why questioning gives you, it doesn’t show you the links between causes and events.

For instance, in our ‘late deliveries on Sunday’ there may be a number of things happening in sequence that prevent on time deliveries, like:

  1. The layout and lack of process means picking takes too long
  2. This late window of time puts pressure on the admin team to raise paperwork and plan routes, too quickly
  3. This means that there are often vital paperwork errors
  4. When the delivery team get the paperwork, they are late already
  5. Because of this, lots of people get fed up and leave
  6. And the new drivers can take longer due to the fact that they are not familiar with the routes and don’t have enough experience to see through the missed fields on the paperwork.

This means that along these sequences, we should be looking at putting various fixes in along the entire processes, so cumulatively the problem won’t appear.

You need to dig down and see all of these links and their relationships.

How to Use 5-why For Maximum Results

Start with 5-why analysis. But don’t stop there. Keep branching out and expanding your analysis as you uncover the data and you walk the process.

Don’t get stuck on the number of questions you ask.

Simply ensure the problem has been given enough thought so it’s been eradicated.

Step 1: Start with the Problem

Be clear what the problem is. Focus on one problem. I recommend starting with something simple, like which goal has been affected. For instance, here are some examples:

  • On time delivery has not been met
  • The safety goal has been missed
  • Profitability has not been achieved

And so on.

Step 2: Answer the First Why

This then leads onto the first of the whys.

Answer this first point and be clear. exactly why the main goal has been missed.

be clear as to each answer.

Step 3: Continue Asking Why

Every answer or sub cause must have one clear point. If it doesn’t, consider splitting them into multiple cause boxes. Here’s what I mean.

See the two factors that come together of which both happened.

These two factors above are totally distinct causes and must be treated as separate events.

Why? Because we will investigate each one.

And each one will have its own branch of cause and effects, which could more than likely end up different to each other.

If you were to just summarise “Errors in shipment weight & missing documents” in one box, you’d miss the opportunity to see deeper and more subtle cause and effect chains and specific causes to events.

Step 4: Keep Expanding Your Why Diagram

Use data and observations so you can keep asking why. Each time expand and branch out.

Keep branching out until you see the problem as a whole

Remember, if an effect needs 4 causes, then add 4 boxes underneath each other. You’ll end up with a comprehensive map of the problem.

It’ll soon be clear to see what parts in this entire map we want to take action on to eliminate their cause and effect relationship – and to eliminate the problem for good..


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