Cause & Effect: Fishbone Diagram & 5 Why’s Hit the Root Cause Properly

Stakeholder Analysis Power Interest

You might know about 5 why’s technique?

You might also know about Fishbone Diagram diagram?

That’s Right! They are BOTH used to identify Cause and Effect relationships.

But do you really know WHY both these techniques are so beneficial to Business Analysis? And even more so in Process Improvement.

And do you really know HOW to use a Cause and Effect, Fishbone template to get the best out of your problem solving skills?

And WHEN to ask 5 why’s? without being abrupt or without just saying, Why? Why? Why? Why? Why?

Well guess what:

In this ONE post.

I’m giving you all this in clear, precise detail.

I’ll also tell you about a project where the Cause and Effect diagram was used to avoid major changes to a system while still obtaining the ultimate time saving benefits.

And it gets even better:

Both these techniques can be used by anyone at any time for any problem.

Whether you're working as a manager, you're at home or even at school.

But wait, there’s more:

By reading and implementing this post, you will have virtually conquered the 8th Business Analyst habit – Problem Solver – as described in my ever-popular post:
Business Analysts 37 Habits: And what you can do NOW – have a read here if you haven’t already.

FREE Bonus Section: Here I give you give you some really cool ways of asking 'Why?' - so you don't sound abrupt but can still master the art of this problem solving technique. Click here to get access.

I don’t Know! What is the 5 Whys and Fishbone Diagram?

OK lets start from scratch:

A cause is WHY something happens.

An effect is WHAT happens.

Practical Problem Solving

5 Why’s is a practical problem solving, questioning technique used to identify cause and effect relationships.

It allows you to get to the root cause of a problem quickly efficiently.

Tanmay Vora offers inspiring uses for the 5 why's technique:
Five-Why Technique for Problem Solving and Decision Making

Visual Problem Solving

A Fishbone diagram is a visual problem solving technique used to identify cause and effect relationships.

It's used by improvement individuals OR teams to brainstorm and logically organise potential causes.

It helps you summarise potential high level causes.

It stimulates the identification of deeper potential causes.

It helps you Drill down further when used together with 5 Why’s.

You might be wondering:

When do we use them?

5 Why’s can be used any time by anyone, it’s simply how you structure your questions and we ALL ask questions at some point.

Fishbone can be used when a more detailed analysis is required for a specific problem.

Knowing this WILL make you want to use these techniques?

If you’re already a Business Analyst.

You know what I mean when I say this.

If you’re not yet a business analyst.

You need to be AWARE of this.


Whenever you speak to a system user or subject matter expert.

They always try to provide the SOLUTION before the REASON for a PROBLEM.

OK maybe not always, but certainly most of the time.

For example:

“The system needs to do this”

“The system needs to do that”

“We need to change this to do that”

As opposed to:

“I’m having this problem and its taking ‘X’ time to work around and its taking ‘X’ amount of resource and this is why…”

At this point, the Business Analyst should be thinking, you haven’t actually told me why you’re having this huge problem! Arrrggghhhh!

So our job is to finish this sentence from “and this is why…”

That’s where these techniques come in and why they are possibly the most important tools in the toolbox.

They WILL enable you to complete this sentence.

And thereby find the right solution for the right causes to the right problem.

A Case Study you can relate to…

To date, I’ve used the 5 why’s technique in at least 90% of the projects I’ve worked on.

The other 10% was before I knew about it 😉


Because you can only get a full understanding of anything by asking why.

But don’t just take my word for it.

The Japanese firm Toyota invented the technique and there are now hundreds of web pages describing the background to these techniques in great detail.

So when did it truly come into effect for me?

When I was working on a project that was to improve a procurement management system.

I was told:

"We need a complete change of system functionality for processing purchasing documents"

5 Why's Speech Bubble

"Because it can take up to 2 hours to process one document."

5 Why's Speech Bubble

"Because we have to match total lines on the document to some of the lines on the Purchases with the same description."

5 Why's Speech Bubbledoes that take so long?

"Because the information has to be calculated manually with a calculator and written down."

5 Why's Speech Bubble

"Because the team member has to go in and out of every purchase line on an order."

5 Why's Speech Bubble

"Because there is no way of calculating all the lines in one go or grouping them together."

You might be thinking…

Asking WHY 5 times is never that straight forward.

And yes, I completely agree.

That’s why in the FREE bonus section I give you some pretty cool ways of getting the same information by using different Why strategies

So if you don’t want to come across abrupt but still want to be hugely effective in your Q&A techniques then download the bonus section here.

You can print it off and read it before a meeting to give you a bit of ‘Dutch courage’.

Yes - Give me better questioning techniques for FREE

But anyway:

As you can see as I dug further into the details, it became clearer and clearer where I needed to focus my investigation.

This was just the beginning.

But it was a great start.

And within just 15 minutes of chit chat. I really did have something to go at.


There has been some criticism over this technique in that it only really touches the surface of root cause analysis.

So armed with my new information, I drew up a cause and effect diagram, organised a quick observation of the process and continued my quest.

You might know that one of the key categories in cause and effect Fishbone Diagram is ‘Information’ (or lack of it).

I soon determined that the root cause was due to the information, which was available in the system. Was not available on-screen at the right time of processing.

The solution?

A quick email to the IT department for them to configure the users screens and show the already-available info on the right screen at the right time – SIMPLES!

The outcome?

A reduction of processing time of approximately 70% for over 95% of credit notes.

This simple change saved £000’s of pounds by not having to go to a 3rd party supplier to have new system functionality developed for processing documents efficiently.

Here’s the bottom line:

If you use the 5 Why’s technique in conjunction with the Cause and Effect (or Fishbone) Diagram.

I PROMISE you will get to the bottom of a problem a lot quicker than if you don't use them.

And I’ll show you exactly how I completed the cause and effect diagram right now.

How to really use a Cause and Effect Fishbone diagram

Armed with your information from the 5 whys.

Or even if you don’t feel like you’ve fully completed your questioning.

You can still begin creating the fishbone diagram.

Which will form the basis of your visual Cause and Effect relationship analysis.

Here’s how...

Step 1. One Problem, One Head

Draw a FISH head

Like this:

Fishbone Diagram - Cause and Effect

Write down the issue or problem statement in the FISH head.

3 rules here:

- Make it a question

- Start with a WHY?

- Keep it narrow and not too detailed

Following these three golden rules will make sure…

1. You can focus your brainstorming

2. If you’re brainstorming with others they’ll quickly know what it’s about.

Step 2. Major Factors

List 5 of the major factors involved

Here are the traditional ‘fishbone’ major factors:

  • - People
  • - Equipment (or lack of)
  • - Method (or process)
  • - Materials or information
  • - Environment

But you don’t necessarily have to stick to these.

You could come up with your own depending on earlier research.

Step 3. Boning Out

Make the bones of your fish and add these as headings for each bone.

Like so:

Fishbone Diagram - Cause and Effect

Step 4. Now for the fun part.

Get your thinking cap on and brainstorm around each heading to place ideas or issues around the relevant header

Drill down into the issues (maybe using 5 why’s hint hint)

Group them into relevant subcategories

Keep going until you have a diagram showing all the possible causes.

At least all those you can think of anyway.

And you will have something that looks a little bit like this:

Complete Fishbone Diagram - Cause and Effect

Step 5. Analyse the Fish’s bone(s)

Look for causes that appear more than once.

Decide if some of them need more investigation or whether you feel like you’ve found your root cause.

Set up investigations, surveys or questionnaires.

Meet with important or relevant people to discuss your findings.

Devise a solution.

Do this and you will never fail as a Problem Solver

When someone comes to you with a problem (or effect)

First ask about the problem using 5 Why’s.

Then develop a Fishbone diagram to list ALL the possible reasons (or causes)

Then do some analysis

Finally use the 5 why’s again to literally HIT the ACTUAL root cause.

But remember it always comes back to the golden rule:

Practice DOES make perfect.

7 thoughts on “Cause & Effect: Fishbone Diagram & 5 Why’s Hit the Root Cause Properly

    1. Thanks Edgar, yes I agree. And it’s certainly easy to try to resolve the symptoms which can have even worse impacts in the long term.

  1. Great Insight Matt. I particularly find the Stakeholders’ Forecast very useful.

    Thank you for the post. Please keep the articles coming.

  2. I still do not see any direct connection between your 5-whys example and your fishbone example. Wasn’t that what this was all about? Also, If the fishbone head is first, then the question was not inserted until diagram #3. Spell it out! Draw a line from your 5 whys to your fishbone and show me the connection.
    Maybe I should start by asking WHY?
    Why does this article miss the mark?

Leave a Reply

Your email address will not be published. Required fields are marked *