Software testing is a process of checking if the actual software behavior meets requirements and matches the expectations. These tests are performed based on the documented requirements of a customer.

But how the software testing (STLC) life cycle looks like?

What is software testing life cycle (STLC)?

Does it have something in common with the software development life cycle (SDLC)?

What benefits do tests provide both to the customer and the team?

Answering these questions and understanding the raised issues may prevent you from software bugs caused by the use of wrong approaches.

The Role of Software Testing in the Software Development Life Cycle

First of all, the software testing process is based on the software development process. Software development life cycle (SDLC) includes the following steps:

  1. Requirements analysis
  2. Design process
  3. Development
  4. Testing process and debugging
  5. Operation and maintenance

As it is shown in the list above, we should perform the required tests is the fourth stage of the life cycle. But usually, if the main goal is to get high-quality software and minimize the cost of bug-fixing, we can apply tests during the requirements analysis phase. The earlier you start the tests, the better results you get.

The Benefits of Performing Tests on Each Stage of the Software Development Life Cycle

Let us show in detail what benefit you can derive by applying the software testing on each phase of the software development life cycle, starting with the first one.

Phase One. Requirements analysis

Let’s start with the first phase of the software development life cycle: requirements analysis. Product requirements are usually outlined by the customer or project manager. These requirements can be functional or nonfunctional. They are formed during the process of communication with the customer or the analysis of standards and normative documents.

Why do we need to perform software testing into this phase of the life cycle, and what benefits we can derive?

Let’s imagine a situation when the existing requirements weren’t tested, but we’ve used them during the design and development stages of the life cycle. Only after development is finished, requirements and the product itself go to the QA team. As it was mentioned above, during the software testing process we check if the actual behavior of the product meets the requirements.

That’s why the QA team finds bugs not only in the product but in the project documentation as well. As you can imagine, in this case, the bug fixing will cost much more comparing to the approach that includes tests into the earliest stages of the software life cycle, like the requirements analysis phase. If you analyze the requirements, you can gather the information that can help you improve the working process from the very first days.

As a rule, requirements testing takes place during the requirements analysis phase. This activity implies checks that based on the characteristics such as completeness, consistency, unambiguousness, etc. The main aim of such approach is to make sure that the customer’s requirements were interpreted correctly and remain correct, understandable and consistent. It is important to note that clear and precise documentation helps to set the right goals for the testing process.

Phase Two. Design Process

The next phase of the software development life cycle is the design process. Just like the requirements testing during the requirements analysis phase, this stage implies checking of the already created prototypes and mock-up regarding their correctness and matching the customer’s expectations.

Moreover, a usability audit should be held during this phase. Also, you should start the creation of the project testing documentation. It’s the preparation of a test plan, test cases, use cases, and some other documentation on customer’s demand. Software testing process at this step helps to provide insights into the product and trace its correspondence to the requirements. There is also a clear vision of activities that should be held by the QA team for this product during all software development life cycle.

Phase Three. Development Phase

During the development phase of the life cycle, it is necessary to hold module, integration, and system testing. At the very beginning of this phase, the module testing is held. It is a process of checking a separate system module or functionality. Integration testing is applied when several modules are brought together and function together as a separate part of the application.

The further software development process brings more modules together. After the development is over, there is time to perform the system tests. This stage of the life cycle implies an overall system check in term of the interaction of its components. It means that if the system consists of different modules, we should check how good or how bad each of them works within the system. Moreover, it is necessary to perform GUI testing at this stage.

Phase Four. Testing Process and Debugging Phase

At this step, you should perform tests whether they were or were not performed during the previous phases of the life cycle. Full functional and GUI testing should be performed, and all founded defects should be documented in a bug-tracking system. Besides that, the regression tests take place, and general quality assessment is provided after debugging is finished. When the last tests are ended, the software testing process is finished.

Phase Five. Operation and Maintenance

Even after the product release stage of the life cycle is reached, there’s still a necessity in testing, which is performed during the operation and maintenance phase. Users can work in absolutely different environments. Thus, it’s always possible that some new defects, that was not detected earlier will be identified during the user’s’ product management. Moreover, users may use the application in some unforeseen way. It can cause some unexpected defects and a QA to review for such cases may require.

Also, read the article Why Software Testing Plays a Key Role in a High-Quality Software Product Development where we considered how the work of an experienced QA team affects the quality of the final product.


It’s obvious that the software testing management process passes through all phases of the software development life cycle. It implies a comparison between the actual state of the product and the one that was planned and documented in the project test plan. Preparation of interim documentation and deliverables is also included in this process. The testing process, analysis, and monitoring help to plan and change further activities properly.

As you can see, the software testing life cycle is a process that cannot be avoided. It’s ongoing, continuous, and requires the QA team experienced enough to perform different QA types of testing. This essential part of modern software development processes helps the customer, team, and end-user to get a high-quality product.