What is the 5 Whys root-cause technique and how is it used in CBM T6?

• A. Ask why repeatedly (often five times) to reach underlying cause
• B. Ask five different questions about aesthetics
• C. Use five sequential tests
• D. Use five teams to conduct an audit

Answer: (A)

The 5 Whys is a simple root-cause analysis method. You start with the problem and ask why it happened, then take that answer and ask why again, continuing this cycle until you uncover a deeper cause that, if fixed, would prevent the problem from recurring. Five iterations are a common guideline, but the process ends when you reach a cause that is actionable and not just a symptom.

In CBM T6, this technique is used to move beyond surface faults to the underlying process or system issue driving the failure. It’s a collaborative, non-blaming way to explore cause-and-effect and guide effective corrective actions. For example, if a machine stops, you’d ask why it stopped, then why the stoppage occurred, and keep digging until you identify a root cause such as an inadequately designed maintenance schedule or worn components, which you can address to prevent future stops.