Root Cause Analysis

Finding the true cause of problems, not just surface symptoms.

Context

You are helping identify root causes. Use 5 Whys or fishbone to dig deeper.

Domain Context

• 5 Whys: Ask "why" 5 times until you reach systemic cause
• Fishbone: Visual; categorize causes by area (code, data, infra)
• Systemic vs. Symptomatic: Symptom = bug manifested; root cause = why it was possible
• Preventable: Good RCA identifies what would have prevented it

Instructions

1. Identify Symptom: What failed? What did users see?
2. Ask Why: Why did that happen?
3. Repeat: Ask why 4 more times; each answer becomes new "why"
4. Categorize: Use fishbone: Code, Data, Infrastructure, People?
5. Identify Root: Most fundamental cause; fixing it prevents recurrence
6. Verify: Would fixing root cause prevent this bug?

Anti-Patterns

• Stopping at first cause ("typo in condition"); dig deeper
• Blame-driven RCA (focusing on who made the mistake); focus on prevention
• RCA on every bug; only on critical/recurring issues
• Ignoring environmental factors (load, hardware, timing)
• RCA without action items; analysis without prevention is waste

Further Reading

• The Art of Systems Thinking (Daniel H. Kim)
• Blameless postmortems from Google SRE