Many people wonder why and how bugs occur in software. A bug is a flaw or failure in a software program that creates a wrong or undesired outcome. It keeps the program from functioning properly. There are several reasons for the bugs, and the common one is human errors in design and coding. Some of the reasons for the presence of bugs in software are shared below.
No Communication or Miscommunication
The success of every program depends upon communication between the development team and the testing team. The main factors that cause defects in an application are ambiguous requirements and misinterpretation of the requirements. If precise requirements are not conveyed correctly to software developers, defects can be introduced during the development phase.
Software programmers are also human, and like most people, they can commit mistakes in programming. All developers are not subject-matter experts. Those who do not have proper knowledge of the domain can introduce mistakes when coding.
Some common reasons why bugs are introduced during the development phase is lack of coding practices, debugging and unit testing.
Usually, the scheduling of software development projects requires plenty of guesswork, and it is difficult. People will likely make mistakes when closing dates are near or at crucial points at which decisions with important results should be made. Unrealistic schedules bring about software bugs, and while not common, these are the main concern during small-scale development.
Poorly Documented Code
Maintaining and changing poorly documented code is tough, and software bugs occur as a result of that. In many businesses, management offers zero incentive for software programmers to write clear and comprehensible code. Instead of incentives, programmers tend to get points for turning out code fast.
New programmers beginning to work on such code may be confused because of the project complexity and badly documented code. Making minor changes in this code can take longer because there is a rather steep learning curve before changing anything.
Software Development Tools
Class libraries, scripting tools, compilers, visual tools, and so forth, can be poorly documented, which result in additional bugs. One of the major ongoing issues is keeping abreast with different versions of software and the compatibility of these versions.
Obsolete Automation Scripts
It takes plenty of time to write automation scripts, particularly for complex scenarios. When automation teams write or record a test script but do not update it during the time they work, that test script could be obsolete and can lead to bugs in software.