Why Code Coverage Matters Even When Tests Are Passing?
Teams often celebrate green test reports, but without visibility into code coverage, it’s impossible to know how much of the application logic is truly being evaluated. Code coverage highlights whether tests are touching critical decision paths, error scenarios, and integration boundaries — not just the “happy flows” that are easy to validate.
A suite with high test pass rates but poor code coverage can give a dangerous illusion of stability. Important logic might remain completely untested, leaving room for regression issues and unpredictable failures in production. On the other hand, tracking code coverage over time helps teams identify testing blind spots, improve risk-based prioritization, and ensure that newly developed features come with safety nets.
The goal isn’t to chase 100% metrics; it’s to use coverage insights as a guide. Strong engineering practices pair coverage analysis with meaningful testing strategies — validating logic complexity, business rules, and performance-critical paths to deliver software that holds up under real-world conditions.