The demand for bug-free, high-quality products is causing sleepless nights for software testers. Using various tools, technologies, and methodologies, testers are driving painstaking efforts to determine the quality, functionality, performance, and other important features of the software – day in and day out.

However, when it comes to functional testing, there are several myths and notions of false ideas that testers tell themselves – to avoid confronting the truth.

First, a baseline definition of Functional testing. This is a type of black-box testing. It tests the software product for its compliance with requirements – as specified by the product owner or client. By evaluating the performance of individual functions of a software application, it ensures the various components and features work as intended – in the real world – and meet the requirements and specifications of clients (and their business).

As testers test core functions of the software product, along with its basic usability, accessibility, and error conditions, testing efficiency is often affected by the myths surrounding functional testing. Here’s looking at 5 such myths:

Myth 1: Functional testing describes how well the product works

Many testers assume functional testing to be a way to test how well a product works. But ensuring software quality is not what functional testing does. Functional testing only describes what the product does; it does not test the software for how well it performs. It tests the software to ensure that it conforms with all requirements and that it possesses all the required functionality that’s specified within its functional requirements. It merely verifies that a piece of software provides the same output as required by the end-user or business and evaluates and compares each software function with the business requirements.

Myth 2: Quality and performance of the product comes under the purview of functional testing

Most testers believe that in addition to testing the functions of the software, functional testing also tests it for quality and performance. However, that isn’t true! Functional testing only tests the software for its functions, usability, accessibility, and error conditions. It verifies that each function of the software application operates in conformance with the requirement specification; it is not concerned about the source code of the application. It only uses the functional specification provided by the client to test the software system against requirements.

Myth 3: Functional testing is a classic example of white-box testing

That functional testing is a type of white-box testing is also a myth many believe. However, that is far from the truth! In reality, functional testing is a type of black-box testing where each part of the system is tested against functional specification/requirements. Testers look to find answers to questions such as – are users able to login to a system after entering correct credentials, or does the payment gateway prompt an error message when an incorrect card number is entered? Unlike non-functional testing that focuses on the internal structure of the code, functional testing checks a product’s functionalities – without looking at what the code looks like.

Myth 4: Functional testing can be executed at the end

A lot of testing teams consider availability and reliability to be far more important aspects of a software product than the functions. Using this notion as a baseline, they end up carrying out functional testing at the end. However, this can prove to be extremely costly (and futile) exercise for development organizations. Since functional testing ascertains if critical functionalities of the product are working fine, and rejects a bad performing application, it needs to be executed first. Only after each functionality of the system is tested by providing suitable input, validating the output and comparing actual results with the expected results, can testers move on to other types of testing.

Myth 5: Automated testing is the (almost) only way to test functional compliance

A lot of times, due to the pressure of bringing products to the market as quickly as possible, testers turn to automated testing to test functional compliance. However, despite all the benefits of automated testing, it has some limitations in the realm of functional testing. In fact, automated testing can cause some bottlenecks in functional verification. It may end up consuming bandwidth that could well be working towards creating quality code. Since modern software is subjected to frequent changes to functionality, automated testing can miss issues that would be easy for human testers to spot. Manually testing many the functional aspects of systems is a viable option in that situation – as it allows a product to be tested in the same way a customer would use it.

Did you believe these myths? If so, it’s time to face reality and win the functional testing battle!