Humans possess unique insights that computers cannot offer, making manual testing more suitable for tasks like usability tests, exploratory tests, and qualitative analysis. Manual testing is best suited for tests that require human intuition, such as user experience-related problems, while automated testing excels in repetitive or routine efforts, like regression tests and performance tests. A balanced approach that combines both automated and manual testing is recommended to maximize return on investment and achieve full product coverage. As an organization's stability increases, the feasibility of manual testing becomes unrealistic, and automation should be prioritized to save time and reduce errors. Larger teams can benefit from automating UI tests to support complex apps with multiple devices and operating system versions.