The 5-Whys Method 

About the method

Whether you call it 5-Why or 5-Whys, it's a method of problem analysis and Root Cause Analysis (RCA). The 5 Why method involves asking Why? at least 5 times in a row, along with 'And what caused that?' in order to delve beneath the various symptoms of a problem and find the real, underlying cause(s).  

Now this can sound blindingly simple.  But thought is required to identify the right questions to ask.

Let's look at an example.

Using the method - an example for a service business

The problem:  A training company delivers specialised training courses to its corporate clients.  A problem occurred on one course:  the wrong course book was printed and delivered to the training venue.  The impact on the course participants (students) was that they didn't have the right book for their course, and it didn't arrive until lunchtime.  The company had to rush to copy the right books, bind them, then deliver them to the venue. The participants were distinctly unimpressed with this, to say the least. It figured highly on their customer feedback sheet.

Applying the method 

1. Why was the wrong course book delivered? 

Andrea usually does this (copying and sending course books to course venues) but she was on holiday.  The fill-in guy got mixed up and produced "Advanced" course books instead of the "Basic" ones for this course. (Symptom)

2. Why did he mistake the course books?

He's only been doing this role for a week.  He hasn't had time to get on top of the job yet, and there's a lot to learn.  (Another symptom - this isn't adequate as a cause, although the temptation for many is to stop here.)

3. If he isn't on top of it yet, why is he doing the job? 

Well, someone has to do it while Andrea is away!  But he did spend some time with Andrea, who went through it all with him before she went on leave.  She thought he'd be OK.  But it does often take a while to get familiar with the various courses and materials, and those two particular courses have very similar names. (Still adding detail, but not addressing the real cause/s yet, though we're getting closer)

4. This isn't the first time we've had wrong course materials delivered, though (nb: this history would be available by checking through the 'problems log/CA register' and form part of the research required to find the real cause/s).  And since we already know it takes a while to learn about the various courses and materials, why don't we have things in place to help that learning?  For example, do we have a packing checklist/instruction for use when preparing and despatching course materials? Does anyone do a cross-check before materials are sent?  Do we have any system for training our people about the various courses and materials we have?

No, we don't. We've been meaning to do stuff like that, but haven't yet.

5. Why not?

Because we've just been far too busy.  And it hasn't been a priority.

Bingo.  Now we've uncovered at least 3 underlying or root causes.  

These are all management practices - weaknesses in the current system of quality management.  They can be changed, and should be.  If not, the problem will happen again; it's just a matter of where and when.

More about the method

Mistakes to avoid
Why use it? 

A systematic approach to mistakes and failures will produce great improvement, no matter what the size of your business or organisation.  That's why any good quality management system should include this, and why the ISO 9001 Standard requires a systematic approach to finding and fixing problems and weaknesses.

If you are still only responding individually and not systematically to a problem, weakness and failure, then you're still in ad hoc and reactive mode.  It's one of the traits of an immature or weak quality management system.  Those with more mature systems are proactive: they've already recognized the rich pickings to be found here, and used an approach such as 5 Whys to improve.

Do aim to collect information on your problems and failures, analyse them and spend time on them.  Because symptoms can crop up in various places and disguises, they may fool you into thinking each is different.  Once you take a systematic approach, you'll often find that various instances are just more of the same symptoms: different details but tracing back to the same root cause/s.

NB: The 5-Why method is closely related to the Cause & Effect (Fishbone) diagram; it is often very effective to use them together.  I rarely use fishbones since I don't much care for them, but some people swear by them.