Test early, test often
When developing software and building features
What Does “Test early, test often” Mean?
Write and run tests continuously throughout development, not just at the end. Early testing catches bugs when they're cheapest to fix and prevents cascading failures. Testing should be continuous, not a final step.
What Happens When You Break It
Delaying testing leads to accumulated bugs, cascading failures, expensive late-stage fixes, fear of changing code, slower development velocity, and customer-facing failures that damage reputation.
Benefits of Following This Rule
Early, frequent testing catches bugs cheaply, enables confident changes, documents behavior, improves code quality, speeds overall development, and reduces production incidents.