The concept of "test coverage" is crucial because it helps to:

The concept of "test coverage" is essential as it directly relates to ensuring that all functionalities of the software are being tested effectively. It measures the amount of testing performed by determining which parts of the code have been covered by tests and which have not. By achieving high test coverage, teams can increase their confidence that the application behaves as expected, and that all features—both major and minor—are functioning correctly.

When test coverage is thorough, it helps to verify that all requirements are met and that any edge cases or specific scenarios have been accounted for in the testing process. This capability is crucial for delivering a reliable product to users and helps in uncovering hidden defects that might exist in untested areas of the codebase. Additionally, ensuring that all functionalities are working as intended is a foundational aspect of maintaining software quality, making test coverage an important metric for software development and quality assurance practices.