Decouple Coverage from Purpose
Don’t plow the whole field to test the soil. In QA, knowing the difference between what you test and why you test changes everything.
A story for QA:
A farmer once owned two fields. In one, he planted wheat; in the other, corn.
When the wheat began to sprout, the farmer wanted to know if the soil was good. Instead of walking into the wheat field and testing the soil there, he brought in oxen, plows, and workers. He had them plow both fields, water them, and wait weeks to see how both wheat and corn responded.
The farmer eventually learned that yes, the wheat field soil was fine - but he wasted time, water, and effort, and the corn crop was trampled in the process.
His neighbor, seeing this, simply scooped a handful of soil from his wheat field, tested it directly, and moved on. The neighbor learned what he needed without disturbing the other crops.
The farmer shook his head. “I wanted to know only about the wheat - but I tested the whole farm.”
Lesson for QA
Many QA teams fall into the same trap. They confuse coverage (what part of the system you’re exercising) with purpose (what you’re trying to learn).
- To check if one service talks to the database, they create sprawling end-to-end tests that drag in half the system.
- To verify a business rule, they go through the UI when the real logic lives in a single function.
- To prove acceptance criteria, they think they must run API tests - even if unit-level tests would suffice.
Like the farmer plowing the entire farm to check one field, the team wastes time, energy, and resources. The result? Slower tests, higher maintenance, and broader failures than necessary.
The lesson: decouple coverage from purpose.
- A business rule can be tested at the unit level.
- A technical check can be run end-to-end.
- The goal defines the test’s purpose; the system level defines the coverage.
When you separate these two, you’ll find your testing becomes faster, clearer, and far more effective.