Benefits of Test Automation


This post lists the benefits of using test automation in your software project.


Testing plays a crucial role in ensuring software quality in software projects. The way testing is done has evolved over the years from completely manual to, in large part, automated testing. However, manual testing is still essential, and automation can take some of the burden of doing repetitive tasks and leave testers more time to spend on other aspects of the system.

With the advent of DevOps and Continuous Integration/Continuous Delivery (CI/CD), testing is now an activity that is integrated throughout the software development process rather than a separate phase. Furthermore, in continuous delivery, the tests must be automated and run as part of the build process. This makes test automation one of the critical enablers for delivering quality software in agile projects.

What is Test Automation?

Test automation means using specialised software tools or scripts to perform testing tasks traditionally done manually. These tasks include running test cases, comparing the results to expected outcomes, setting up test preconditions, and other test control and reporting functions. Test automation usually requires writing code for the tests, albeit sometimes, off-the-shelf tools can be used.

A software project requires several types of tests to achieve good coverage due to the nature of each test type:

  • Unit testing tests individual units of source code
  • Integration testing tests the integration of two or more software modules or components
  • Functional testing tests the functionality of the software

Software developers usually write the first two, and the third can be implemented by automation testers or testers and developers together. Other tests use software tools, such as performance and load testing, but this post concentrates on functional testing.

The Benefits of Test Automation

Increased Efficiency and Productivity

Software and applications can be rather complex and have a multitude of features. Testing each and every one of the features is very time-consuming and error-prone when done manually. In addition, each feature requires several test cases to cover potential situations the users of the application will see, for example, input data or environmental differences.

Testing all these combinations occasionally is doable, but very few software projects get completed and never get any updates. This is especially true for agile software development projects using continuous delivery, where developers commit new code daily. Therefore, the tests must be executed repeatedly to ensure the software still works as it should.

Improved Accuracy

Getting all the tests right manually takes a lot of focus and precision from the person executing the tests, even for a single test run. In addition, repeating the same tests over and over again and expecting testers to be able to work this way for a more extended period is quite a tough ask.

Test automation doesn't lose focus and doesn't make mistakes. However, the person who wrote the tests can make mistakes, and the tests aren't perfect by any means, but they provide mainly repeatable results for as long as the CI runs them.

Team Confidence

Knowing that a safety net in place will catch most errors will allow the development team to work confidently on things such as refactoring code and other significant modifications. Any code change could cause severe defects without the tests, increasing the team's stress level. The effect is similar to the case where code is rarely deployed to production, where the team is afraid to deploy as they don’t have the routine to do it.

Faster Feedback

When the automated tests run on a CI pipeline for each commit in a pull/merge request, the developer immediately gets feedback for potential problems. It allows for catching issues before they are merged into the main codebase.

Each test failure also provides feedback, usually an error message, that can help determine what went wrong. Error messages in the test output and a test report showing passed and failed tests help to see problems with the tests and what's being covered.

Allows testers to concentrate on other things

When many of the mundane, repetitive tasks have been automated, the testers in the team can concentrate on high-value testing, such as exploratory testing, to find problems in unusual circumstances or other situations that weren't considered from the get-go.

One task will be adding new automated test cases when a defect slips through the net or a requirement is unclear initially.

Lowered Costs

It is easier to calculate the saved time in not having to execute the same tests manually repeatedly by summing up the work hours that would have been spent. What's more difficult to estimate beforehand is how much money is saved when users are not selecting a different provider due to software issues or if the system goes down due to a severe defect when the proper test coverage is not in place. Another dimension is the potential reputation damage caused by software problems. While it's difficult to estimate, I'm going out on a limb and claiming that having good test coverage will be worth it in most cases.

Higher Test Coverage

Test automation increases test coverage in multiple ways. First, the tests can be executed quickly and repeatedly, enabling the running of many cases. Tests can cover many data-driver test cases by iterating over data inputs that can be generated automatically. Tests can also be repeated in different environments with different characteristics. For example, hardware configurations, operating systems, software versions and settings

Secondly, as mentioned in the previous paragraphs, manual testing is time-consuming, and there won't be enough time to cover all the cases for every build. To release anything, you'll need to pick a subset of tests (smoke test) to execute, and there is a potential for bugs in the remaining untested functionality.

Also, test automation suite coverage can easily be extended by writing new tests. Once the tests have been implemented, they will run as part of the test suite on the CI without extra effort. Of course, you'll always have to be mindful about testing things on the correct test layer, as running too many end-to-end tests takes more time and can start to cause problems with test reliability.

When testers don't need to execute repetitive low-value test cases, they can concentrate on things that bring higher value to the team, thus increasing the test coverage and potentially finding defects in the system.

Enables Continuous Integration/Continuous Deployment (CI/CD)

As mentioned earlier, automated tests are crucial in enabling continuous integration and continuous delivery. In addition, automating the tests is the only way to get from a code commit to deployment quickly.

Each commit can potentially cause problems with the application or site, and having enough test coverage to feel confident about a deployment to production is crucial. Of course, it isn't easy to know how much coverage is enough, but to me, a good measure is precisely that: feeling confident about deploys. It is okay if a quick manual smoke test is required to feel good about the deployment, but the bulk of the testing has to be automated.

Enhances Collaboration

Tests can enhance collaboration in multiple ways. One of the main tools is using Behaviour-driven Development (BDD), which allows developers, testers, and other stakeholders to work on defining the acceptance criteria and the scenarios used for testing the feature even before the feature is implemented.

In BDD, the scenarios are written from the application user's point of view using business language instead of specifying technical implementation details. The technical details can be handled in the unit or other lower-level tests, and it is essential to keep the BDD scenarios written in a way that allows stakeholders to be part of defining them.


Testing has evolved from purely manual to predominantly automated, making software projects more efficient and accurate. In addition, with the rise of DevOps and Continuous Integration/Continuous Delivery (CI/CD), testing is now a continuous activity critical for maintaining quality in agile projects.

Test automation should be a part of the team's workflow, enabling the team to deliver better code in less time. Test automation code is not written at the project's beginning or end but continuously during the project delivery.