Five Whys Analysis

What Are the Five Whys?

The Five Whys is a root cause analysis technique. You keep asking "why" until you reach the fundamental cause, instead of stopping at surface symptoms.

Process

1. Define the Problem

Clearly state the issue or symptom

2. Ask "Why?" Five Times

• Why did this problem occur? → Answer 1
• Why did Answer 1 happen? → Answer 2
• Why did Answer 2 happen? → Answer 3
• Why did Answer 3 happen? → Answer 4
• Why did Answer 4 happen? → Answer 5 (Root Cause)

3. Validate Root Cause

• Verify the logical chain
• Check if addressing root cause prevents recurrence
• Consider multiple root causes if applicable

4. Develop Solutions

• Address the root cause, not just symptoms
• Create preventive measures
• Consider systemic improvements

Example: Application Crash

Problem: Application crashes when processing large files

1. Why? → The application runs out of memory
2. Why? → It loads entire file into memory at once
3. Why? → The file parser wasn't designed for streaming
4. Why? → Initial requirements only specified small files
5. Why? → Requirements gathering didn't consider future growth

Root Cause: Incomplete requirements gathering process

Solution: Implement streaming parser and improve requirements process

Example: API Response Slow

Problem: API endpoint taking 10+ seconds to respond

1. Why? → Database query is slow
2. Why? → No index on the queried column
3. Why? → Schema migration didn't include index
4. Why? → No performance review in migration process
5. Why? → Migration checklist is incomplete

Root Cause: Incomplete migration checklist

Solution: Add performance review step to migration process

Best Practices

• Focus on process, not people - don't blame individuals
• Look for systemic issues - find structural problems
• Document the analysis - record the full reasoning chain
• Involve relevant stakeholders - get the right people in the room
• Test solutions address root cause - verify your fix actually works

Applying Five Whys in Vibe Coding

When AI-generated code has issues, Five Whys can pinpoint what went wrong:

Problem: AI generated code doesn't compile

1. Why? → Using wrong syntax for the framework version
2. Why? → AI assumed older framework version
3. Why? → Prompt didn't specify framework version
4. Why? → No project context provided
5. Why? → Missing CLAUDE.md or context-prime step

Root Cause: Missing project context

Solution: Always run /context-prime before complex tasks

Five Whys Template

## Problem Statement

[Clear description of the issue]

## Analysis

### Why #1

Q: Why did this happen?
A: [Answer]

### Why #2

Q: Why did [Answer #1] happen?
A: [Answer]

### Why #3

Q: Why did [Answer #2] happen?
A: [Answer]

### Why #4

Q: Why did [Answer #3] happen?
A: [Answer]

### Why #5

Q: Why did [Answer #4] happen?
A: [Answer - Root Cause]

## Root Cause

[Summary of the fundamental issue]

## Proposed Solutions

1. [Solution 1]
2. [Solution 2]

## Preventive Measures

-   [Measure 1]
-   [Measure 2]

Next Steps

Check out Mermaid Diagram Generation to visualize your analysis results.