WHAT IS THE DIFFERENCE BETWEEN MANUAL AND AUTOMATED TESTS?

When it comes to testing a product, the question may arise: manual or automated testing? To answer this question, it is important to first understand the differences between them. 

In recent years, more and more companies have embraced test automation as a way to accelerate product launches and the deployment of new features, while optimizing the productivity of their technical teams. But functional test automation has its limits, which is why manual testing still has a bright future ahead of it. 

Both manual and automated functional testing have their advantages and disadvantages, and the choice between the two depends on several criteria: financial, temporal, material and project requirements. In this article, we will try to differentiate these two practices, while demonstrating that there is a complementarity that should not be put aside.

Manual testing 

Let's start with manual tests. As the name suggests, they are executed manually, i.e. by a human. This human can be a tester, a digital project manager, a developer, etc. Their role: to put themselves in the shoes of an end user to perform each action and verify that everything behaves according to the expected results. 

In manual testing, there are both guided tests and exploratory tests. In the case of a guided test, the scenario is written and a path is predefined indicating each step to be verified. In the case of an exploratory test, the idea is to discover the product like an end user. The actions are not predefined and the verifications are performed spontaneously. The interest here is to test scenarios that we had not thought of. 

The automated tests

Automated functional tests are carried out by "robots" , using tools and/or software and following a set of specifications established beforehand. 

There are several automation levers. The first is to automatically execute predefined actions, such as clicking on a product page, adding it to the shopping cart, logging into the account, filling in shipping information and proceeding to checkout. The second is to verify specific functionalities, which have a higher or lower level of criticality and which can have a direct impact on the business. In both cases, the objective is to detect possible bugs in order to correct them as soon as possible.

What are the advantages and disadvantages of both practices? 

Before choosing between manual or automated tests in your project, you should list the strengths and weaknesses. 

The advantages of manual testing include low budget, random testing and optimal user experience. But they are more time consuming and not as accurate as automated tests, because a human can make mistakes and this makes them less reliable than a robot. In addition, it is not always possible to test the application on different operating systems. 

On the other hand, automated functional tests have the advantage of being faster, more frequent and on a larger scale. They can be performed more easily on different operating systems, devices and browsers. They improve move-to-prod and reduce time-to-market, are more reliable and the reporting of anomalies is more efficient. 

Moreover, the development of technological functionalities allows for the automation of new customer paths, such as graphic comparison, digital security keypads or tests via API.

But automated functional tests require a higher investment and are complex to set up. They also have some limitations. Indeed, it is not possible to automate everything. For example, it is possible to automate certain accessibility tests, particularly in terms of checking the presence of tags in the front-end code, but they cannot be automated 100%. Exploratory tests, because of their randomness, are also difficult to automate without using an AI capable of understanding an application by itself. 

Manual and automated tests, should you choose? 

The two approaches are in fact complementary. Indeed, as we said in our article " How to choose what to automate", the automated functional tests, although quite successful, are not sufficient in themselves to provide a complete and relevant evaluation of an application. It is necessary to combine manual and automated tests to ensure the quality of web or mobile application development and thus obtain an optimal return on investment! 

Thus, it is more interesting to automate recurring and repetitive tests, as well as functional tests that concern criticalpaths and functionalities, or those that require to be performed on several browsers and/or devices. We can also add non-regression tests, which allow us to verify that the modifications made have not impacted previously existing functionalities.

But some tests need to remain manual, because the fact that they are run by a human allows them to spot things that a machine would not see, especially regarding usability, accessibility, etc. And, as we said above, exploratory tests are more reliable when done manually. 

In conclusion, the objective you should have if you aim at industrializing your testing activity is Automation of all recurring tests and non-regression testsThis allows manual testing effort to be devoted solely to the validation of new features. 

What about you, what are your thoughts on the subject? Tell us in comments!