What is 5-why analysis?
The 5-Why analysis is a problem-solving technique that seeks to identify the root cause of a problem by repeatedly asking the question “why?” five times (or as many times as needed) to peel back the layers of an issue. The basic idea is that by the time you’ve asked “why?” for the fifth time, you should be close to identifying the underlying cause of the problem.
Here’s a simple step-by-step explanation of how the 5-Why analysis works:
- State the Problem: Clearly describe the problem you’re facing. It’s essential to be specific and focused on one particular issue at a time.
- Ask “Why?”: Investigate why the problem occurred. This will lead you to an initial cause.
- Repeat: Based on the answer to the first “why?”, ask “why?” again to dive deeper into the cause.
- Continue the Process: Keep repeating the “why?” question until you’ve either identified the root cause or reached a point where the question can’t be answered.
- Analyze the Root Cause: Once you’ve identified a root cause, validate whether addressing this cause would prevent the problem’s recurrence.
- Implement and Monitor: Take corrective actions to address the root cause and monitor the results to ensure the problem doesn’t happen again.
Here’s a basic example:
Problem: The car won’t start.
- Why? – The battery is dead.
- Why? – The alternator is not functioning.
- Why? – The alternator belt has broken.
- Why? – The belt was well beyond its useful service life and not replaced.
- Why? – The car was not maintained according to the recommended service schedule.
Root Cause: The car was not maintained according to the recommended service schedule.
While the technique is called the “5-Why” method, in practice, it might take fewer or more than five questions to reach the root cause. The key is to persistently question each level of cause until you’ve identified the underlying issue. Additionally, it’s essential to be cautious and avoid oversimplifying complex problems, as sometimes multiple root causes might be at play.