Manual Testing Vs. Automated Testing: Which One Is The Best Fit For You?

In the life of every project, there comes a moment when an application gets too complex, and manual testing resources are just not enough to produce a quality application. At this point, a project manager may face a dilemma: should they grow the manual testing talent, take a leap into test automation, or maybe combine both approaches.

Below, we cover everything you need to know to solve the manual vs. automation testing riddle for yourself.

Let’s start with the basics.

Manual vs. automation testing — what’s the difference?

Manual testing

During manual testing, a test engineer mimics the behavior of a real user and manually checks whether an app under test behaves as it should. While doing so, a QA engineer may either rely on test scenarios and test cases — the instructions defining what to test and what behavior to expect from an app — or let their mind wander freely in search of non-trivial bugs.

The types of testing that call upon a human touch span:

• Exploratory testing: As the name suggests, this type of testing relies on the tester’s free exploration of the test item. A tester leverages their domain knowledge, creativity, and previous experience to detect uncommon defects that can be overlooked during formal testing.
• Ad-hoc testing: This type of testing needs no preparation and doesn’t require a tester to follow any specific test design techniques or execution workflows. The goal of ad-hoc testing is to find defects by randomly checking the application’s functionality.
• Usability testing: For usability testing, the human perspective is vital. A tester evaluates whether an app is easy and convenient to use and measures users’ satisfaction with the application.
• Low-volume regression testing: The goal of regression testing is to ensure that recent changes introduced to software haven’t affected the existing functionality. For that, a test engineer reruns all or some of the already executed test cases. In short-term projects with a small number of tests to run, manual regression testing is a cheaper and more flexible way to go.

A common misbelief has it that the key factor underlying the manual vs. automation testing dilemma is the reliance on tools. In reality, manual testers use various software tools that help make manual testing more agile and reliable and vary from testing documentation management to cross-browser testing apps. Here’re the most frequently used of them:

• Tools for managing testing documentation. These help conveniently create, manage, and modify test cases, as well as record and track test results. Some tools offer an opportunity to generate reports on test runs, team workload, and test coverage, too. The most popular testing documentation management tools include TestLink, Zephyr, TestLodge, and others.
• Defect management software. Such software helps manage defects, keep all of the defect data in one centralized space, facilitate communication within the project team, and notify team members of changes. The prevalent issue management tools include Jira, Trello, BugZilla, and RedMine.
• Cross-browser testing software. With the help of cross-browser testing tools, testers verify whether an app runs equally well across browsers, devices, and platforms, manually checking the response levels. The well-known tools span CrossBrowserTesting, SauceLabs, LambdaTest, and others.
• Email testing tools. These tools help make sure an app’s email functionality is working correctly by offering an opportunity to view how emails render in different email clients. So, testers may skip having to install multiple email apps and sign up to numerous accounts. The popular tools include Litmus, Mailtrap, Putsmail, Email on Acid, Stripo, and others.

Test automation

Let’s now dig into the second component of the manual vs. automation testing pair. Test automation aims at running more tests in less time. For that, test automation engineers develop test scripts for automated test execution. Designed based on frequently executed manual test cases, test scripts allow running multiple checks simultaneously, with no human assistance.

There are two common approaches to test automation: API-level testing and UI-level testing.

With API-level testing (or integration testing), testers ensure that the requests sent to the software’s business logic and other applications integrated with the test item are handled correctly.

UI-level testing, in turn, stands for checking software’s functionality via interacting with its UI elements. For that, test automation engineers can either develop custom automated test scripts or turn to visual comparison tools that allow analyzing an app’s UI against its previous version.

So, what are the types of testing that are worth automating?

High-volume regression testing is the number one candidate for automation. Although it requires some preparation to set up an environment for running automated checks, design a test automation ecosystem, and develop test scripts, the time saved outweighs the initial investments.

Here’s an example from Slava Markovski, QA automation expert at ITRex, to support this statement: replacing manual regression testing with test automation in a project dealing with insurance software featuring complex calculations allowed the team to reduce the regression testing runtime from two weeks to just two hours.

To ensure your test automation initiative yields guaranteed time and cost savings, it is better to evaluate the need for automation and start rolling out test automation activities, like preparing the needed environment and developing first tests scripts, at the beginning of a project.

Another type of testing worth automating is performance testing, though it lies outside the immediate area of responsibility of test automation teams and is usually executed by performance engineers. To test the response times, throughput, resource utilization, stability, and scalability of an app, performance engineers simulate the behavior of several simultaneous users to check an app’s performance characteristics.

While developing test scripts, test automation engineers rely on tools that serve different purposes and span:

• UI-level test automation frameworks. These tools help verify the functionality and the user interface of an app by ensuring all of its controls, like menus, buttons, links, text boxes, and other elements look and work as expected. UI testing tools popular among testers include Selenium WebDriver, Protractor, WebdriverIO, and others
• Unit testing tools: Unit testing helps verify the quality of an app’s code at the early stages of development. Although used mainly by developers, unit testing tools can be of help to test automation engineers as well. Test automation teams leverage unit testing tools, like NUnit, TestNG, Jasmine, JUnit, Microsoft unit testing framework, and Mocha, to set off automated script execution.
• Mobile testing tools: These tools are designed specifically to simplify the testing of mobile apps, both native and hybrid. Many of the mobile testing tools available on the market allow writing tests for multiple OSs and support scriptless test creation. Appium is the most popular mobile testing tool that offers support for multiple platforms and languages.
• CI/CD tools: These tools help build highly efficient delivery pipelines by aligning development and test environments. So, any code changes introduced to the software are verified immediately or in batch at a set schedule. The common CI/CD tools include Jenkins, CircleCI, TeamCity, and others.
• Reporting tools: These tools allow generating test reports for test automation teams to visually present the results of test runs and see how they evolve. Report Portal and Allure are among the widely used ones.

Manual vs. automation testing — is the latter better?

According to a recent survey, only 12% of companies have full test automation in place, and 35% are halfway there, meaning more than half of the surveyed organizations have little to no test automation. While prioritizing manual testing is justifiable for small and mid-sized organizations, overlooking automated testing in large-scale projects with high volumes of tests limits companies from tapping into many benefits. If you’re navigating the automation vs. manual testing problem, check our recent article to get an in-depth look into the benefits of automation testing.

And here’s a quick overview of those worth a mention:

• Higher test coverage. Due to simultaneous test execution, test automation allows running more tests in the same amount of time. And while manual testing can only cover a certain number of devices and OSs, test automation scripts can be easily extended to more devices, platforms, browsers, and operating systems with little to no effort, thus helping unlock more defects.
• Speedier and more efficient testing. The ability to run multiple checks in parallel and shift a larger share of tests “to the left” — that is closer to the start of the development lifecycle — allows to make testing more agile and provide feedback on the quality of an app way faster. And with automation testing integrated into a CI/CD pipeline, testing may even become continuous so that developers get immediate feedback on the quality of changes.
• Reusability and scalability. Automated tests can run unattended, so you can schedule tests to run during out-of-office hours, saving work time for the tasks requiring a human perspective. Also, test automation frameworks allow rerunning test scripts and deploy checks for multiple users and environments.
• Reliable test results. Automated testing is reliable and resistant to human error. Moreover, some rare bugs can only be discovered during parallel testing. Our test automation team, for instance, spotted an app returning the 500 error when several simultaneous users submitted refund claims, which would have been difficult to detect with manual efforts only.
• Optimized testing costs. Test automation helps detect more bugs earlier in the development cycle when they are simpler and cheaper to fix. On the contrary, with manual testing, a larger share of defects gets discovered closer to the end of a sprint, which often leads to delayed releases and incurs additional costs.
• Fast generation of test data. For well-rounded testing, abundant and representative test data is crucial. Test automation helps generate sufficient volumes of test data through a series of simple API calls.

Challenges in automation testing to look out for

To tap in all the benefits above, you have to plan your test automation adoption journey carefully. Here’re common issues you may face in automation testing and some ideas you can use to solve them:

• Time and effort investments. Creating, managing, and updating test scripts takes both knowledge and time. And as software grows, so do test script management efforts. But you can take those efforts to a minimum if you pay close attention to the scalability of your test automation ecosystem from the very start. It may take an experienced test architect to design the ecosystem. Still, it is worth it in the end — a skilled test automation engineer can help roll out a test automation initiative in one to two weeks, making sure test scripts are easy to maintain.
• Accessing the right talent. Test automation requires specific skills, so if you’re lacking the right competencies, you’ll have to decide whether you would hire test automation engineers, breed the team in house, or turn to a QA outsourcing vendor for vetted test automation talent. No matter the option you choose, you would have to put in the time to get your test automation initiative up and running talent-wise.
• Balancing costs. Developing and maintaining test scripts and using test automation frameworks incur additional costs. To get a guaranteed pay off, it is crucial to follow a balanced test automation strategy. Ensure your software is stable, start with automating a small share of regularly executed regression tests, and grow your test automation suite step-by-step.
• Tackling false positives and false negatives. When approached carelessly, test automation can, too, be subject to errors. Both false positives (detecting bugs that do not exist) and false negatives (missing bugs that do exist) may halt the test process. To combat both, set some time aside to review your test scripts and see if they are in tune with recent software changes. This will help reduce the risk of errors to a minimum, keeping your tests fresh and preserving trust in your test suit.

Manual testing vs. automation testing: so, what’s the deal?

Manual testing and automation testing are not mutually exclusive. In fact, both approaches work best when balanced according to the size of your project and the complexity of the software under test. Still, test automation is a more cost-effective, efficient, and reliable way to go in large-scale, long-lasting projects.

Check out the table below that summarizes everything said above to sort out the way out of the manual vs. automation testing problem for yourself.

The difference between manual and automation testing:

Don’t let the manual vs. automation testing dilemma halt your deliveries. Drop ITRex team a line, and their testers would set up the test process that’s just right for you!