In this lesson, we'll review the basics of root cause analysis using the 5 Whys.
Root Cause Analysis & the 5 Whys
Root Cause Analysis is the process of digging into a problem to solve it at it's root. Often, we are looking for a quick fix so we address the symptoms of a problem without digging into the root cause. As a result, the problem persists and we continue to waste time addressing only the symptoms.
The most common, and easiest to use, Root Cause Analysis tool is the 5 Whys. It’s simply asking "why" until you get to the root cause.
How to Perform Root Cause Analysis
1. List out the undesirable outcomes of your problem or process
- environmental permit approvals are taking longer than the 2 week goal
- 15% of all financial reports have a defect or incorrect calculation
- customers are not satisfied with how long it takes to set up their new accounts
2. Ask "why does this outcome occur?" or "what's the cause of this result? List out of the drivers or "whys"
3. Select one of the drivers from Step 2. Select the one that the team feels has the biggest impact on the problem. Ask, "why does this occur?"
4. Drill down and continue asking "why" until you have reached a root cause that the team can address.
5. As time allows, go back and select another driver from Step 2.
So, when do you stop?
There is no magic to the number of whys. Stop when you get to the root cause! That's easy to say but a little more challenging in practice.
Here are two good guidelines on when to stop asking why:
1. Stop asking "why" when you get to the absurd or you start explaining the universe
This is when your team will get frustrated and roll their eyes at you. There is no way that the problem is under your control or you could ever find a fix.
2. You've reached a point where you could reasonably solve the problem and prevent it from recurring
Simply ask the team, "if we fix this problem, do we think we can prevent the undesirable outcome from happening again?" If yes, stop there and start discussing potential solutions.
Be careful not to blame the people performing the process. Simply hiring a new employee or providing re-training to existing will not solve your problems. Look for ways to improve the process itself - mistake-proofing, process redesign, defined roles and responsibilities, etc.
A famous example of the importance of the 5 Whys is the Jefferson Memorial in Washington, DC. The Memorial started deteriorating because chemicals were regularly being used to clean it.
Undesirable outcome: deterioration of the Jefferson Memorial.
1. So, why was the Jefferson Memorial deteriorating?
In other words, why does this outcome occur?
Because harsh chemicals were being used to clean it.
2. Why were harsh chemicals being used to clean it?
To wash away the bird poop.
3. Why was there so much bird poop?
Because the birds like to hang out and eat the spiders.
4. Why are there so many spiders?
The spiders like to come out and eat midges (little bugs).
5. Why are there so many midges?
The midges are attracted to the Memorial’s lights and go there to mate.
Solution: Change the lighting to reduce the number of midges.
You can see if they stopped too early, they wouldn't be solving the root cause. And you can see that if we had to ask "why" one more time (why do midges need light to mate? or why do midges mate?), we'd start explaining the absurd.
Do you know the true root cause of your problem?
Dig in to the 5 Whys with your team and try to drive to the root.