When to Use Test Automation vs. Manual Testing Techniques

In software quality assurance, testing ensures that applications, websites, and mobile devices function as expected. However, choosing between test automation and manual testing techniques can be challenging. Both approaches have distinct advantages, and knowing when to apply each is key to optimizing efficiency, cost, and coverage in your testing strategy.

1. Test Automation: Speed and Repeatability

Test automation involves writing scripts or using tools to automate repetitive tasks in software testing. It is especially beneficial when tests need to be run frequently or across various platforms. Automated tests are fast, reliable, and capable of executing large volumes of tests in a fraction of the time it would take manually.

When to Use Test Automation:

• Regression Testing: Automating regression tests is highly efficient. After making changes or updates to a software application, it’s important to ensure that previously developed functionalities work as intended. Automating these tests ensures consistent, rapid validation without manual intervention.
• Performance and Load Testing: Testing a system’s performance under a specific workload is nearly impossible to conduct manually. Automation allows QA teams to simulate thousands of users interacting with an application simultaneously, critical for website load testing and e-commerce testing, where real-time performance metrics are essential.
• Repetitive Testing: Scenarios requiring repeated testing of the same workflows or features across different data sets or environments are ideal for automation. For example, running application testing scripts for various input conditions or environments can quickly provide wide coverage.
• Cross-Browser/Device Testing: Automated scripts can test web applications across multiple browsers and mobile devices, ensuring compatibility without manual intervention. This is especially relevant in mobile device testing, where tests need to be run across various operating systems and hardware models.
• Continuous Integration and Continuous Delivery (CI/CD): Automation is indispensable in CI/CD pipelines, where tests are triggered automatically with each code change. This approach allows teams to receive fast feedback, key to maintaining software quality assurance over time.

2. Manual Testing: Flexibility and Human Insight

Manual testing involves human testers manually interacting with the software. This approach provides flexibility and insight that automation cannot replicate, particularly in areas requiring subjective judgment, exploration, or interaction.

When to Use Manual Testing:

• Exploratory Testing: Manual testing is critical during the early stages of development or when a new feature is implemented. Testers manually explore the software to identify unexpected issues or behaviors. This form of testing is highly creative and best suited for uncovering defects that aren’t easily caught by predefined automated tests.
• Usability Testing: Manual testing is crucial when assessing how user-friendly an application is. It evaluates the software from a user’s perspective, allowing testers to spot design, user experience, and functionality issues that automation would likely miss.
• Complex Test Cases: Some test cases are too intricate or require human judgment, such as tests involving complex business logic or those that assess visual elements. For instance, during website testing, visual design, layout, and responsiveness are critical; a human eye can better catch nuances in alignment, typography, or other UI aspects that automated tools might overlook.
• Short-Term Projects: Setting up automated tests might take more time and effort when the project timeline is short, or changes are minimal. While test automation is a powerful tool, it requires its development effort to support it, making it expensive and unwieldy in the short term.  In these cases, manually testing a few specific areas is often faster, especially for smaller or one-off tasks.
• Ad-Hoc Testing: Also called exploratory testing, ad hoc testing involves unscripted applications. It requires a human touch to ensure that the process is representative of actual potential use and to interpret the expected test results. Ad hoc testing is extremely effective in finding deficiencies overlooked by more structured and repetitive testing, but it needs to be better suited to test automation.

3. Combining Test Automation and Manual Testing

The best approach often involves combining test automation and manual testing techniques to achieve optimal results. This hybrid approach allows testers to leverage the speed and coverage of automation while using manual testing for flexibility and human insight.

Best Practices:

• Prioritize Automation for Repetitive and Regression Tests: Automate tests that need to be run frequently and consistently. This can include tests for core functionality, performance metrics, and security checks.  Automated test cases should be developed early, and changes should be tracked as they are made.
• Manual Testing for New and Uncharted Features: Manual testing should take precedence in areas where user interaction, user experience, or newly introduced features are involved. Early-stage development and exploratory testing benefit greatly from human creativity and judgment and complement the development of automated tests by providing essential feedback on core design features.
• Regularly Review Test Cases for Automation: As the application matures, more test cases can be automated to reduce the manual testing load. However, regular reviews are essential to ensure automated tests remain relevant and reflect the current state of the software.  Likewise, manual tests can inform a team of what changes need to be made to automation to support an application’s lifecycle. Front-end changes can often drastically affect the workings of automation and require test cases to be updated continuously.

Conclusion

Both test automation and manual testing are essential components of software quality assurance. The decision to use one technique over the other depends on the nature of the project, the complexity of the software, and the specific testing requirements, such as whether it’s for application testing, website testing, or mobile device testing. 

Automation excels in repetitive, large-scale, or performance-related tasks, while manual testing excels in areas that require human intuition, creativity, and judgment. Balancing both ensures comprehensive testing coverage, higher-quality software, and more efficient resource use.

Contact Beta Breakers today to learn further and experience the advantages of these two software testing approaches.