Root Cause Analysis

Root Cause Analysis Orchestration Skill

This skill helps you systematically identify the root cause of any problem using proven methodologies from the Toyota Production System and other industry-standard techniques.

Quick Reference: When to Load Which Resource

Core Principle

Do not treat symptoms—find and fix the root cause. As Taiichi Ohno, architect of the Toyota Production System, said: "By repeating why five times, the nature of the problem as well as its solution becomes clear."

Orchestration Protocol

Phase 1: Problem Classification

Quickly identify your problem domain and complexity:

Problem Domain:

• Software: Code bugs, system failures, performance, deployment
• Hardware: Equipment, mechanical, electrical, maintenance
• Process: Workflow, procedures, organizational, communication
• Personal: Life challenges, productivity, habits, wellbeing

Complexity Level:

• Simple: Clear failure chain, 1-2 likely causes → Use 5 Whys
• Complex: Multiple possible causes, unknown scope → Start with Fishbone
• Critical/Safety: High stakes, needs rigor → Use Fault Tree
• Multiple Issues: Many competing problems → Use Pareto first

Action: Load appropriate resource file(s) based on classification.

Phase 2: Methodology Selection

Based on problem type, select your approach:

Phase 3: Execution & Verification

During Analysis:

1. Define problem clearly (What/Where/When/Impact)
2. Gather evidence systematically
3. Apply selected methodology
4. Document reasoning at each step
5. Verify root cause with Forward/Backward tests

Before Finalizing:

• Validate conclusion against evidence
• Check for red flags (see common-root-causes.md)
• Confirm actionability (can you fix this?)
• Develop solutions addressing root cause

Problem Definition Framework

Create a clear problem statement before analysis:

Essential Elements:

• What: Observable symptom (not assumed cause)
• Where: Location/system/component affected
• When: Timeline, frequency, pattern
• Impact: Users/systems affected, severity

Example: "Users in EU region experience 3-5 second dashboard load delays during 9-11 AM UTC peak hours, affecting ~2,000 daily active users. Started after v2.4 deployment on Nov 18th."

Evidence Gathering (Go and See)

Follow Toyota's principle—collect facts, not opinions:

Key Evidence Sources:

• Logs, metrics, monitoring data
• Timeline of events and changes
• System/code/configuration changes before problem
• Environmental factors (load, traffic, season)
• User reports and reproduction steps
• System state before/during/after

RCA Methodologies

See resources/rca-methodologies.md for complete methodology guide.

Resource Files Summary

resources/rca-methodologies.md

Comprehensive methodology guide covering:

• 5 Whys: Step-by-step process with software examples
• Fishbone Diagram: Structure, 6 M's categories, process
• Pareto Analysis: Prioritization using 80/20 rule
• Fault Tree Analysis: Top-down formal analysis
• Barrier Analysis: Control failure examination
• Structured 6-phase RCA process, domain-specific guidance, templates

resources/common-root-causes.md

Pattern reference catalog by domain:

• Software Engineering: Code defects, configuration, dependencies, deployment
• Hardware & Equipment: Mechanical, electrical, operational, maintenance
• Process & Operations: Workflow, design, resources
• Personal/Life: Health, habits, environment, skills
• Red flags, recurring themes, pattern recognition

resources/example-analyses.md

Four worked examples with full analysis:

1. Software Bug: JWT authentication (5 Whys)
2. Vehicle Maintenance: Overheating (5 Whys)
3. System Failure: E-commerce checkout (Fishbone + 5 Whys)
4. Personal Productivity: Missed deadlines (Fishbone + 5 Whys)

resources/advanced-techniques.md

Formal methods for complex problems:

• Fault Tree Analysis: Boolean logic, safety systems
• Barrier Analysis: Control failures
• Multi-Methodology Chains: Complex orchestration
• Verification Frameworks: Comprehensive testing

How This Skill Works

1. Clarify your situation: Domain, observations, evidence, time
2. Recommend approach: Complexity analysis, methodology, resources
3. Guide through analysis: Problem statement, evidence, methodology, verification
4. Deliver output: Analysis, root cause, solutions, implementation

Quick Start: 5-Minute RCA

1. State problem (What/Where/When/Impact)
2. First Why: fact-based answer
3. Second Why: dig deeper
4. Third Why: dig deeper again
5. Verify: would fixing this prevent it?

Templates & Examples

• 5 Whys Template in resources/rca-methodologies.md
• Fishbone Template in resources/rca-methodologies.md
• Worked Examples in resources/example-analyses.md
• Solution Structures in resources/example-analyses.md

Next Steps

1. Identify problem domain (software/hardware/process/personal)
2. Load appropriate resource from table above
3. Select methodology based on complexity
4. Follow step-by-step process in resource
5. Verify root cause (Forward/Backward tests)
6. Develop actionable solutions

Remember: Goal is systematic investigation—disciplined questioning until you reach a cause you can actually fix.