The ‘5 Whys’ tool provides a simple, straightforward method to get to the heart of a problem.
Too often we’ll look at the symptoms of a problem, and fail to take the extra time needed to identify the root cause.
Tools like the ‘5 Whys’ template have saved companies millions of dollars by refocusing the company’s philosophy to fixing underlying issues rather than fix problems.
Taking the time to get to the root causes underlying the problem will hopefully keep the problem from happening in the future, rather than just slapping a ‘bandaid’ on it today.
Remember the old proverb, “for the want of a nail the kingdom was lost…”
The ‘5 Whys’ root cause template has been around since the 1930’s, invented by Toyota founder Kiichiro Toyoda’s father Sakichi, and made popular in the 1970’s as part of the Toyota Production System.
Today, the method is used extensively in many productivity and problem solving systems including ‘Lean’ and ‘6 Sigma.’
Why use the ‘5 Whys’ tool?
While simple to use, a 5 Whys root cause analysis lets you, or your team, start mining down to the heart of the problem. As it doesn’t take any special tools beyond a white board, it’s also an inexpensive way to look at your problem.
How’s it work?
It’s really as simple as the name suggests. By asking ‘Why’ over and over, you’re peeling the onion back until you reach the ‘real’ problem. Though straightforward, the tool is incredibly effective.
Problem – My car won’t start
1. Why? The battery is dead
2. Why? The alternator isn’t working
3. Why? The alternator belt is worn
4. Why? The alternator belt hasn’t been replaced per the car’s maintenance schedule
5. Why? I didn’t know there was a maintenance schedule, because I didn’t read the manual
What would happen if we had failed to keep asking ‘Why’ and stopped at an earlier step?
1. The battery is dead
Solution: Charge or replace the battery
Result: The new battery would have died because the alternator isn’t charging
2. The alternator isn’t working
Solution: Replace the alternator
Result: The new alternator wouldn’t work because the he belt is too worn to properly turn the alternator
3. The alternator belt is worn
Solution: Replace the worn belt
Result: The current problem would be fixed, but would happen again, because the owner still isn’t aware of the requirement to replace the belt regularly
4. The alternator belt hasn’t been replaced per the car’s maintenance schedule
Solution: Owner learns the alternator belt needs to be replaced every 50,000 miles
Result: This will fix the current problem, but others will occur because the owner isn’t aware of the car’s maintenance schedule
5. The owner didn’t know there was a maintenance schedule, because he didn’t read the manual
Solution: The owner reads the manual, including the maintenance schedule
Result: Problem solved!
We can check our solution by going backwards, using ‘Therefore’ instead of ‘Why’…
Turning the ‘5 Whys’ around and using ‘Therefore’ will show us that we’ve worked the solution back to the original problem.
I didn’t read the manual fully
Therefore, I wasn’t aware of the maintenance schedule
Therefore, I didn’t replace the alternator belt per the maintenance schedule
Therefore, the alternator belt wore out
Therefore, the alternator stopped working
Therefore, the battery died
Therefore, my car won’t start
While simplistic, the ‘5 Whys’ is a powerful tool that requires you to keep digging until the real (root) cause of the problem is answered. Keep in mind this is flexible, and you may find the root cause may be found at the third ‘Why,’ or it may take 6 or 7 ‘Whys’ to get to the real solution.