root-cause-analysis

# Root Cause Analysis

Systematic problem solving using Fishbone (Ishikawa) diagrams and 5 Whys technique. Identifies true root causes and recommends effective corrective actions.

## What is Root Cause Analysis?

**Root Cause Analysis (RCA)** is a structured approach to identify the fundamental cause(s) of problems, rather than addressing symptoms. Effective RCA prevents problem recurrence.

| Approach | Focus | Best For |
|----------|-------|----------|
| **Fishbone (Ishikawa)** | Brainstorming all potential causes by category | Complex problems with multiple potential causes |
| **5 Whys** | Drilling down through cause chains | Problems with linear cause-effect relationships |
| **Combined** | Fishbone to identify, 5 Whys to drill down | Comprehensive root cause identification |

## Framework 1: Fishbone (Ishikawa) Diagram

### What is a Fishbone Diagram?

A **Fishbone diagram** (also called Ishikawa or cause-and-effect diagram) organizes potential causes into categories, resembling a fish skeleton with the problem as the "head."

```text
        ┌─────────────────────────────────────────────────────────┐
        │                                                         │
  Man ──┼──┐                                         ┌──┼── Method
        │  │                                         │  │
        │  └─────────────────────┐   ┌───────────────┘  │
        │                        │   │                  │
        │                        ▼   ▼                  │
        │                    ┌─────────┐                │
        │                    │ PROBLEM │                │
        │                    └─────────┘                │
        │                        ▲   ▲                  │
        │  ┌─────────────────────┘   └───────────────┐  │
        │  │                                         │  │
Machine ┼──┘                                         └──┼── Material
        │                                               │
        │