Both business titans and young startups have the same intention to ensure that every buck of their investments will turn into something worthy. The only way to ensure that all the efforts and resources weren’t wasted is quality management provided by experienced specialists. In the case of custom-made software, the whole quality concept is pretty complex since it includes both the functional and non-functional aspects. It’s not enough to find every single error in the source code. To make sure that the final product is worth of your investments, you should also test the ways of user interaction with it.

The complexity of the software quality assurance process has led to a wide variety of software testing services that we can divide into two big groups: manual testing and testing automation. In this article, we’ll focus on their main features, benefits, and drawbacks to help you find the optimal way of delivering a top-notch software product.

The Difference Between Manual And Automated Testing

Before going any further, let’s outline the main differences between manual testing and testing automation.

Manual testing, as the name suggests, is performed by hand. According to the software features, a set of test cases is created, and QA specialists follow them to ensure that the app works properly. The manual testing approach is pretty useful when there’s the need to test some aspects of the app that can’t be tested by computers. In a nutshell, manual testing implies that the app will be used on multiple devices in conditions as close as possible to the end user’s world.

Testing automation, in its turn, implies the use of a bunch of scripted tests that run automatically to check if the app works according to expectations. Testing automation is irreplaceable when there’s the need to execute a vast number of recurring tasks. For example, a QA specialist can simulate thousands of server requests to check how well the app can work under high loads. There are dozens of automated software testing tools such as Selenium, for example, that can simplify the web application testing process across multiple browsers and operating systems.

In most cases, to guarantee the excellent quality of the final product, you have to combine these two approaches to software testing. Manual tests and testing automation complement each other and guarantee that the app will work as expected and won’t cause confusion among the end-users.

Manual Testing. Suitable For Short-Term Projects, Minor Changes, and GUI-oriented Apps

Manual testing, despite its seemingly primitive nature, is an essential part of the quality management process and, therefore, can’t be underestimated. Usually, manual testing is performed before the automated testing. It requires many efforts comparing to automated testing but allows ensuring that automation is possible. Sometimes, you can limit your testing activities and run manual tests only, which will help to save time on testing automation. For example, a simple web site or an application that will not be used by a large number of users usually won’t suffer much if you perform manual tests only. Contrariwise, a product with a strong emphasis on UI/UX will benefit from manual testing. The reason is simple. It’s pretty hard for a computer to tell if a particular font on a specific page of the app is poorly read by a human end-user of just looks weird due to bad color combinations.

The following tests are performed manually:

  • Ad-hoc testing is executed without any preparations and pre-written test cases. It implies the checking of random app functions in order to break the application and find possible flaws;
  • During the exploratory testing, a QA specialist explores the application relying on personal experience and creativity. Unlike the ad-hoc testing, this approach requires test cases written after receiving the full picture of the app’s functionality;
  • Usability testing is necessary to ensure that the application is convenient for end-users;
  • User interface testing helps to validate the properties and states of interface elements under different circumstances.

As you can see, in some cases, we can’t rely on a bunch of scripts running by a computer, especially in the case of user interface conveniency and usability.

When You Should Choose Manual Testing

Each tool has its field of application. There are some cases in which manual testing will be the best option to guarantee the quality of the final product. UI Acceptance is one of the examples. Manual testing is an excellent choice when it comes to user interfaces and various visual aspects of the application. Automated testing doesn’t allow to define if current colors of UI elements, font size, and highlighting look great and don’t confuse the users. During the initial development stage, when investing in testing automation may not be so rational, manual testing allows detecting possible bottlenecks and helps reduce further efforts on bug fixing. In the case of short-term projects such as small web sites, testing automation may be pretty labor-intensive. Therefore, saving time on creating testing scripts in favor of manual testing may be the right decision. Last but not least, there are some non-automatable cases. For example, some mobile apps should be tested manually to check if smartphone sensors work as expected.

The Benefits of Manual Testing

Testing an app manually, you’re as close to the real-life environment as possible. QA team checks how software behaves in real-life scenarios, which helps to get the full picture and capture bugs and flaws with which a regular user can face while working with the app. A thorough design review can’t be provided by automated testing since this approach doesn’t provide full information on the application’s look and feel. A QA specialist, on the other hand, can perform manual tests to ensure that the application is easy-to-use and has an excellent user interface. Lower costs can be achieved thanks to the lack of investments in any testing tools.

The Drawbacks of Manual Testing

Risks of failure is a price that you have to pay if you rely on a human mind. People can miss some errors and flaws in the design, which can result in unpleasant consequences. Manual testing requires more resources and time. The manual approach is slower if we compare it to testing automation. Also, it requires more investments that will increase as your project grows. After a new feature is released, you have to retest the whole product to make sure that nothing is broken. You can’t test everything manually. Imagine that you want to test how your app works under high loads. With testing tools, it’s not too hard to simulate 1,000 users trying to access the application simultaneously, but hiring 1,000 testers to do the same job will be a harsh task.

Automated Testing. For Long-term Projects With Frequent Updates And High Performance

Testing automation is irreplaceable for large projects that can’t be tested manually. Complex software systems that take months and years to complete contain a tremendous amount of code and functions. Every minor change can affect various parts of the application, which makes it barely possible to test everything by hand. Testing allows the QA team to test the whole product at every iteration without any significant efforts. If you rely on data processing and high performance rather than on attractive UI, you can benefit from test automation.

Testing automation is best applied to the following types of tests:

  • Unit testing that implies the testing of discrete parts (units) of the whole software system;
  • Regression testing helps to ensure that your software system performs as expected after modifications or integration with other apps. Automated testing is pretty helpful if your codebase changes frequently. This approach can save your resources with multiple test scenario reruns;
  • Functional testing is performed to help the QA team to detect the actual performance of an application’s functional requirements;
  • Load and performance testing, with the help of testing automation tools, allow even a single QA specialist to simulate thousands of end-users working with the app simultaneously.

These are the common testing automation techniques that can reduce the demand of people and time without sacrificing the quality of the final product. Besides, this kind of testing can decrease the risk of the human factor.

When You Should Choose Testing Automation

The primary purpose of testing automation is to help the QA team handle time-consuming and repetitive tasks. After you made changes to a software system, you have to check that it works. If it works. Testing all the app’s functionality manually over and over again will cause significant delays in development. By running automated regression testing, the QA team can detect new bugs without any considerable effort. Also, testing automation can reduce the probability of human error. Using testing automation tools and scripts, QA specialists decrease the chance of missing a bug and make the whole process more efficient. Besides the app’s look and feel, there are differences in behavior between different browsers and platforms. GUI testing automation helps to detect these differences and effectively find regression errors. There’s no alternative to testing automation when you want to test load and performance.

The Benefits of Manual Testing

First and foremost, testing automation is a quick and effective approach. Once set up and configured, the testing framework can handle all the work almost autonomously. Tests can run on multiple computers and browsers, reducing time and effort. Reduced costs for long-term projects is another benefit that testing automation can provide. QA team members can add more test cases as your project grows, and there will be no need to hire extra staff. Testing automation provides better transparency. The use of dedicated tools allows share testing results among the QA team members, which provides better collaboration and visibility.

The Drawbacks of Testing Automation

In the case of testing automation, to buy a license for the testing tools and set up a proper testing process, additional costs are required. In a long-term project, further maintenance and reconfiguration of these tools is another important issue. These expenses should be considered when you plan the development process. If you choose testing automation only, you won’t receive an unbiased opinion on the usability of your application and its UI. To make sure that the end-user will feel comfortable while using your application, you still need to perform some manual testing. The companies that develop testing automation tools may not know about your needs and the features of your product. Therefore you can face some testing tools limitations and bugs. Fortunately, QA specialists can customize used scripts according to the needs of a particular project.


In most cases, it’s barely possible to tell if manual or automated testing should be preferred to guarantee the quality of the software product. The truth is that both of these approaches to software testing have multiple benefits and complement each other. Testing automation can guarantee that your application has no bugs and runs smoothly under high loads, but a great app is more than just the source code. Another important aspect is the way users interact with the app. The curious human nature may give rise to use cases unobvious for those who develop testing tools. Perception features also play a role. What looks normal for the testing script may confuse the end-user, and manual testing is the exact tool to avoid it. Therefore, to guarantee the quality of the software product, both manual and automated testing should be used alongside the whole development life cycle.

To learn more about software testing and its impact on your project, feel free to contact us.