M07DiagnoseDiagnosis· Module 2
Finding the Root Cause
The first explanation is usually a person. The real cause is usually a system that lets the failure repeat.
- Fix
- Stabilise
- Operations
- Leadership
- ~5 min · Worksheet
The business problem
When something goes wrong, the quickest explanation is individual error. Replacing or warning the person rarely stops the failure because the conditions that produced it — unclear instructions, missing checks, conflicting priorities — remain in place for the next person.
Why it matters
Root-cause analysis turns failures into permanent improvements. It also changes the culture: people report problems when they know the aim is to fix the system, not to find someone to blame.
What you will learn
- Use the 'five whys' and cause-and-effect analysis on a real failure
- Separate individual error from system failure
- Test a proposed cause against evidence before acting
- Design countermeasures that prevent recurrence
Core questions
- Would a different, competent person have made the same mistake?
- What made the failure possible, and what failed to catch it?
- What evidence confirms this is the cause?
- What change would make the failure difficult to repeat?
Work through the module
CaseWhat is happening?
Pharmacy chain, 6 branches · Illustrative teaching case
A pharmacy chain finds expired stock on shelves in two branches. The first response is to issue warnings to the branch staff. A root-cause review shows that deliveries are shelved without rotating older stock, expiry dates are not recorded in the system, and no one is responsible for a monthly expiry check. The same risk exists in all six branches.
DecisionWhat does the leader need to decide?
Discipline the staff involved, or change how stock is received, recorded and checked across all branches?
FrameworkHow should they think about the problem?
Five whys and the cause-and-effect diagram
Ask why the failure happened, then why that happened, until you reach a cause the business controls. A cause-and-effect (fishbone) diagram widens the search across people, methods, materials, equipment, measurement and environment.
ToolWhat can they use?
Root-cause worksheetWorksheet
- Describe the failure precisely: what, where, when, how often
- Ask 'why?' five times, recording evidence for each answer
- Check each category: people, method, materials, equipment, measurement, environment
- Choose a countermeasure that prevents, not just detects, the failure
ApplicationHow does it apply to their business?
Apply it to your own business:
- Pick a failure that has happened at least three times
- Complete the worksheet with the people closest to the work
- Decide on one preventive countermeasure
ImplementationWhat changes?
What should change in the business:
- Put the countermeasure into the process, not only into a memo
- Assign an owner and date for completion
- Add a check that would reveal whether the failure recurs
ReviewDid it work?
How to tell whether the change worked:
- Has the failure recurred since the countermeasure?
- Were similar failures elsewhere also reduced?
- Are staff reporting problems earlier than before?
After this module you should be able to decide
Discipline the staff involved, or change how stock is received, recorded and checked across all branches?
And leave with: A root-cause analysis for one recurring failure.
Sequence · Diagnosis