Map vs Territory
The description of the thing is not the thing itself.
Explanation
Any description or model of reality is necessarily simplified—the menu isn't the actual meal, the business plan isn't the actual business, and the weather forecast isn't the actual weather. We often forget this and mistake our simplified models for reality itself. Philosopher Alfred Korzybski warned: 'The map is not the territory.'
Real-World Example
GDP says economy is great, but people are struggling (map vs reality). Your code's documentation is perfect, but the actual code has bugs. Dating profile (map) vs actual person (territory). Company org chart shows clear hierarchy, reality has shadow power structures. Financial models showed mortgage securities were safe; 2008 proved otherwise.
How to Apply
When map and territory conflict, trust territory. Update maps regularly—they decay. Before important decisions, check: Am I looking at data (map) or experiencing reality (territory)? Get into the field: talk to real customers, not surveys; try the product, don't just read specs; visit the factory, don't trust reports. Remember: more detailed maps are still maps, not reality.