Automation testing is crucial for large projects to achieve test coverage and speed. It is best suited when tests are repetitive, such as regression testing of unchanged parts of an application. Automation allows companies to execute repetitive and difficult tests faster to get quick feedback on new builds. However, automation requires significant investment and effort, so it is best to start with critical workflows that are stable and unlikely to change. Leveraging a crowd testing platform can help combat challenges in achieving full test coverage through a strategic combination of in-house and crowd-sourced testing.