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.
- Process controls are inadequate. There is no cross-check, to make sure things are done consistently, even if the person doing the task is new to it.
- Lack of documentation. No priority has been given to writing down important information, such as which course books are required for which particular course. Rather than a system, the company has relied upon Andrea knowing the job and being there to do it.
- Lack of systematic training. There is no effective internal training system in place, to make sure this important function of delivering the right course materials to the right course is covered properly during staff absence. And this may well apply to absences in other key roles as well.
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
- The answer to the first Why? question should point the way to the next one.
- You cannot just race straight through all questions in a few minutes, asking and answering all questions immediately. Unless perhaps you are very experienced in the method, and the solution is relatively simple. For example, you may need to gather and analyse more information in order to decide what question to ask, or to get the answer. And you may need to stop and think about whether you're asking the right question(s).
- By the time you get to the fourth or fifth Why…? and if you have asked the right questions, you should be close to the root cause or causes. You'll then have identified management practices rather than just symptoms.
- 5 questions is the 'classic' number of questions to ask; it was the number set by Toyota who pioneered this method. In practice you may find you need more or fewer. This will depend on the importance and severity of the problem. Asking too few may mean that your analysis is too shallow. Conversely, asking too many questions may mean you're going into over-analysis and losing sight of the goal.
- There is usually more than just one single cause for a problem. That means you'll need to review the causes uncovered, identify what needs doing to resolve them, and of course determine which you will action and their priorities.
- The method is valuable, but requires practice to do it well. As with other improvement tools, the more you use it, the better you get.
Mistakes to avoid
- Don't confuse symptoms with root causes. This is by far the most common mistake. Symptoms are outward signs that there's a problem, but they are not the real causes. The fact that the fill-in guy 'didn't know' there were two courses with very similar names is only a symptom of an underlying problem. It is not the real cause. In a management system, people don't fail, but processes do.
- Don't settle for the siren call of the simple answer. Most people stop way too early in a problem-solving process and latch on to the first or second simple answer. Again, they confuse symptoms (such as the new guy not knowing something) with the real underlying cause/s. The first 'cause' offered is virtually never the real cause. But it's only when you find a root cause that you can take effective corrective action and remove that real cause. And thus stop that problem cropping up again.
- Don't believe there's only one single root cause. One potential weakness of 5 Whys is that it may lead to that belief. But far more often than not, there's more than one cause contributing to the problem.
- Don't settle for blame. If I had a dollar for every time that 's/he made a mistake' or 'it was just human error' has been given as the cause of a failure, I'd be rich. Very rich.
- Yes, we're all human and yes, of course mistakes happen. But don't stop there! People experienced in quality management know this and design processes and systems around this knowledge, building in sensible controls to prevent, avoid or worst, catch errors. Because 99.9 times out of 100 the problem lies is in the system itself. Which is also good news, because management systems can and should be improved.
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.
Author: Jane Bennett