Manual or Automated Testing: Which is Better?
Why do we need software testing in the first place? Software testing is adopted to find out the errors and faults in the software developed for business functions and utility. The test results will provide us the areas in which the improvement is needed. To yield the best results, it is necessary for the software to meet the very objective and the purpose for which it was developed.
A software testing tool should have a wide/good coverage, which means that it should be well-designed (with the maximum possibilities of finding the errors). With good coverage, we mean that the testing is to be done in various areas like functionality, compatibility, performance and load testing. Overall, the software testing tool should be reliable (with minimum chances of crashing) and that it should be easily deployed to any machine without any resistance.
Key Differences Between Automated and Manual Testing
Software testing is an extensive process, but it can be broadly divided into two sectors – manual and automated testing. Understanding the differences between the two is important to test a product successfully within an optimal budget.
Manual testing is required for all testing projects. It is the first step even when testing involves automation. Automated testing, on the other hand, is an optional part of testing projects. Projects do not start with automated testing, but should consider it at the planning stage for its advantages in certain areas.
Speed: Automated testing is significantly faster than manual testing once set-up. Manual testing requires more time and manpower in the long run..
Setup Time: Although automation is faster while running tests, it requires script preparation before it can be started. The same doesn't apply for manual testing. Testers can start as soon as they get the project.
Dependency: In manual testing, there is a higher dependency on human resources while lower in automated testing. This is because automated testing relies on tools more than people.
Reliability: Manual testing does not guarantee reliability as humans are prone to making errors. Automated testing, on the other hand, repeats exactly the same test operations each time, making them far more reliable, that is assuming the script is well written in the first place.
Work Nature: Manual testing can be laborious for the tester as the same processes have to be repeated. Errors occur in the same test because of testing fatigue. However, when writing a new automation test, the tester's mind has to be more involved. This makes test automation more interesting.
Teamwork: Manual testing does not allow the whole team involved to look at the results. Test automation makes it easy for team members to view test results by just logging in to the testing system. This promotes teamwork.
Real World Bugs: Automated testing runs only a set number of tests and, because of that, cannot replicate real world scenarios effectively. Meanwhile, manual testing can find bugs that an actual user might experience after the product launch.
Flexibility: As automation is robotic and needs codes to be written for specific functions, it is not easy to change the course of a test mid-way. But a manual tester can implement his own thoughts and ideas without much delay.
Short-Term Expense: If the testing requirement is short-term, test automation would be too expensive. Automation tools would have to be bought, and a tester would have to spend the time for initial setup writing scripts. A manual test would be a more economical choice under such conditions.
Long Term Cost-effectiveness: In the long run, automating your tests is far more cost-effective than manual testing. Automated tools do more work in a given time and find more bugs consistently. This makes it beneficial to employ automated testing in larger or repeating projects.
Limitations: Not all testing can be done by automated tools. Testing visual elements such as font size and image color require manual involvement.
When to Use Manual Testing
Random Testing: This kind of testing is done without any planning. The aim of ad-hoc/random testing is to break the system and thereby check the viability of the product. This is usually done only once, mostly done during scientific experimental studies.
Usability Testing: Emulating real-world situations is next to impossible for automation tools. Human observation and analysis are must-haves to know how a product works in such test cases.
Exploratory Testing: When the test project does not have set patterns or proper specifications and has time limitations, it requires a tester's experience, intuition, creativity, logical skills and knowledge. Automation does not have any scope in such projects.
Security Testing: Most security testing is designed to purposely hack the system and find vulnerabilities. This is best done with manually.
When to Use Automated Testing
Performance Testing: When testing requires simulating hundreds or thousands of simultaneous users, manual testing would be very difficult.
Repeated Testing: Large test cases that require the same tasks to be run repeatedly are best done using test automation.
Regression Testing: When an already developed software (after it is integrated with another software) needs to be tested for ensuring optimal performance, it is best to make use of automation tools.
Load Testing: Testing is done to know the behavior of a system under different levels of workload. The key parameters checked are resource usage, scalability, and reliability. For an efficient load testing, automated testing is the best choice.
While both manual and automated testing have their pros and cons, effective software testing warrants judicious use of both types of testing.