Software Testing: Why is it so Difficult?

From: SoftwareProjects.org

Software testing is probably the most complex task in the software development cycle. It often takes longer to test the software than it does to write the code. The problems discovered during the software testing phase add more time onto the coding phase, resulting in further delays in the product’s release, and so this vicious cycle goes.

It’s nearly impossible to attribute the problems that arise during the software testing cycle to any single factor. Before going any further, it’s important to clarify one point. Software that works, but not the way it is supposed to work, is not considered an error in the coding (also known as a bug). Rather, this situation is the result of an error in the design phase. Software engineers refer to these differences as a “fault” vs. a “failure”. Faults can turn into failures, but that’s a subject for another time.

So why is software testing such a time-consuming and frustrating process? One factor is the complexity of the software being developed. The more complex the project is, the more there is to test. Also, complex projects typically involve multiple development team members, including those working directly for the company and those working as sub-contractors.

Software testing troubles directly attributable to the human factor include poorly documented code and employee turnover. And if the person who is not properly documenting the project is the same person who leaves the company midway through the project cycle, the problem quickly compounds.

Another software testing difficulty arises when those developing the software are the same ones testing that software. These individuals have a much higher level of understanding about software and computer system. They’re not likely to make the same types of mistakes during the software testing phase that end users might make using the finished software. For example, software engineers understand that you never press the power button before you properly close all applications. End users, in their rush to burst out of the office at 5:00 pm just want the computer off, and some won’t wait until every application closes properly.

Plenty of software testing applications are available to help during the software testing phase. These products are designed to facilitate and enhance the software testing phase, provided they can be made to work with the software being tested.

The main purpose of software testing is to discover software failures. As failures are discovered, they can be corrected. However, software testing cannot guarantee that the software is problem-free. Testing finds many bugs, but even the most extensive testing processes can’t fix failures that are not uncovered. Never rely on software testing as proof that no problems exist. That’s considered software verification, an entirely different process.

Regardless of the difficulties involved with software testing, one truth remains. Software failures discovered early on cost far less to correct than those that occur in latter stages of software development, or worse, after the software has been released to the general public.