Bug Root Cause Finder

Systematic methods for finding the true source of bugs, not just symptoms.

Core Principle: Symptom ≠ Cause

The location where an error manifests is rarely where the bug originates.

Error Location:     OrderController::show() - NullPointerException
Symptom Location:   OrderRepository::find() - returns null
Root Cause:         OrderCreatedHandler - failed to persist order
True Root Cause:    RabbitMQ message lost due to missing ACK

Method 1: 5 Whys Technique

Ask "why" repeatedly until you reach the root cause.