In software development – everyone is responsible for quality. That being said, the skills and mindset required for a good test engineer are entirely different from the ones needed for a good software engineer. It is not always best for developers to perform test automation. 

Read on to learn why it is better for automation testing to be conducted by test engineers (whenever possible).

Why is Automation Testing Significant?

Test automation is an essential part of software development as it helps speed up the development lifecycle process. By automating test scenarios, team members have more time to focus elsewhere, allowing them to save time and money. It also provides better test coverage and ensures that regressions are often found early in the development cycle.

Unconscious Bias

Developers are well familiar with the code they have written. It is only natural that this leads to unintentional bias when writing test scenarios. Their familiarity with the code can lead to a lack of objectivity. They can “be sure” that something is working correctly and that there is no need to cover this part of the application with tests. This point of view can be very menacing to the quality of the application. We should always be careful and question everything multiple times to ensure it always works as expected.

Test engineers usually don’t have the same familiarity with the code (especially if they perform black-box testing). They are often better placed to write test scenarios and confirm that all features are equally covered with tests.

Focusing on the Happy Path

Test engineers’ critical mindset is a skill developed, and it improves with time. The more experience a test engineer has, the better they “attack” a feature and test it. This means they understand and know more ways to “break” the testing functionality. They are testing if the functionality is working as intended but are also focused on what could go wrong, not only on what is supposed to go right. Their primary focus should be on finding problems.

A developer’s mindset is different as their primary focus is on finding solutions for problems. Often, they are focused on how a functionality should work and not necessarily on what could go wrong. Their tests usually follow the “happy path” or the “happy flow,” where they focus on the correct implementation of the functionality.

It is equally as important to test both – check if the new feature is working as intended by the requirement and how the software responds when it is not used as intended. Focusing on only one or the other can lead to poor test coverage.

Multi-Level Validation Instills Better Quality.

In software development, it is always better for every task to go through more hands and be checked by different people before reaching the customer. 

If one team member writes up requirements, others should check and validate those requirements before development starts. If one team member is writing code to implement these functionalities. In that case, other team members should check if the code is working correctly. If one team member is writing test scenarios to test the software, other team members should challenge those test scenarios and see if there is anything else to add to improve the test coverage. 

This approach allows for better quality and validation of the software, guaranteeing that more issues are found and fixed while still in the development process. Once the software is delivered to a customer, these issues become more expensive to fix.

So if the developer is writing and testing their code, we are losing on this multi-level reviewing and validation, which brings multiple benefits to the team.

Conclusion

These are just some of the reasons why it is essential always to have test engineers implemented in the testing process.

As mentioned, the decision on who will write the tests lies within the team and depends on the context. If the test engineers in the team don’t have the technical skills required to create the automated tests, they should at the very least be included in the conceptualization of the scenarios to minimize the bias and allow for the second level of review.

Remember, one thing is always true in software development – everyone is responsible for the quality.