Using Metrics to Discover Testing Holes` Metrics can help discover testing holes by providing valuable data on bug tracking tools. By analyzing metrics such as the source of bug tickets, it's possible to identify areas where change is needed and understand what tests are effective. Bug tickets can be triggered at various stages of a feature's development lifecycle, including automated scripts, design audits, smoke tests, and exploratory tests. A well-implemented bug tracking tool with fields like Issue Source can help track these metrics and provide insights into the effectiveness of testing practices. By using metrics, teams can determine if new processes are successful and make data-driven decisions to improve their testing strategies.