# Root Cause

> Dig to fundamental truths and real causes behind problems. Use when user asks "why does this happen", "what's the real problem", "root cause", "first principles", "jobs to be done", "JTBD", "five whys", "fundamental reason", or needs to understand underlying causes rather than symptoms.

- Skill: `majiayu000/root-cause` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds add majiayu000/root-cause`
- Raw SKILL.md: https://api.skillmd.com/api/skills/majiayu000/root-cause/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: majiayu000 (https://skillmd.com/u/majiayu000)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/majiayu000/root-cause

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# Root Cause - Fundamental Truth Finder

Dig beneath symptoms to find fundamental causes and truths. Stop treating symptoms and solve actual problems.

## Quick Start

1. Identify what you're trying to understand
2. Select technique based on what you need
3. Keep digging until you hit bedrock

## Technique Selection

| Need | Use | Why |
|------|-----|-----|
| Understand why a problem occurs | Five Whys | Chain backward to root cause |
| Challenge assumptions, rebuild from scratch | First Principles | Strip away conventions |
| Understand what users actually need | Jobs-to-be-Done | Focus on underlying motivation |

**Default**: Use Five Whys for problems, JTBD for user needs, First Principles for innovation.

## Techniques

### Five Whys
Chain backward from symptom to root cause by repeatedly asking "why?" until you hit fundamental cause.

Read [cookbook/five-whys.md](./cookbook/five-whys.md)

### First Principles Decomposition
Strip away assumptions and conventions to find fundamental truths, then rebuild solutions from basics.

Read [cookbook/first-principles.md](./cookbook/first-principles.md)

### Jobs-to-be-Done (JTBD)
Understand what users are really trying to accomplish, not what they say they want.

Read [cookbook/jobs-to-be-done.md](./cookbook/jobs-to-be-done.md)

## Core Principles

1. **Symptoms lie** - Surface problems often hide deeper causes
2. **Keep asking** - First answer is rarely the root cause
3. **Challenge assumptions** - "That's just how it works" isn't an explanation
4. **Multiple roots** - Problems often have several contributing causes
5. **Verify** - Test your root cause hypothesis before acting

## When Root Cause Analysis Works Best

- Same problem keeps recurring
- Fixes don't stick
- Problem feels like "that's just how it is"
- You're solving what customers ask for, not what they need
- Starting something new and want to avoid inherited assumptions

## Warning Signs You Need This

- "We've tried everything but the problem persists"
- "That's how we've always done it"
- "Users say they want X" (but X doesn't seem to help)
- "We fixed that already" (but it came back)
- Solving lots of small problems instead of one big one