Why Are Tests Essential?

2 minute read

Software testing is a fundamental aspect of any successful software development project. It is the process of examining a system or system component to determine whether it meets specified requirements. But why is it so important? Let’s delve into the reasons.

Ensuring Correct Functionality and Handling Edge Cases

Software tests are a critical source of feedback. They answer two essential questions:

  • Are all functionalities working correctly?
  • Will our software behave correctly with atypical data and edge cases?

By addressing these questions, we can ensure the system’s efficiency and reliability. We can also ascertain that the software will handle unexpected scenarios effectively, reducing the likelihood of failure during real-world use.


Errors and system failures can be costly, and fixing them post-production can be even more expensive.

According to a report, the global cost of errors and system failures in IT was over 3.3 trillion dollars in 2002. By 2018, this figure had risen to 1.1 trillion dollars in the USA alone. By implementing effective testing strategies, we can reduce these costs substantially.

Facilitating Changes Safely and Efficiently

Testing also aids in the smooth and secure implementation of changes to the software. It minimizes regression, preventing the occurrence of errors in functionalities that previously worked correctly. Testing is particularly beneficial when new team members unfamiliar with the project or certain areas make changes. The testing phase can catch any unintentional errors or oversights, ensuring the software’s consistency and integrity.

Living Project Documentation

Another notable advantage of software testing is that it serves as a living document of the project. It provides insights into how the system actually works and can conveniently export reports for business use. Moreover, there’s potential for automatic generation of user documentation from the test code, adding to the project’s efficiency.

Fast Debugging and Better Communication

Testing enables quicker debugging of code snippets, eliminating the need to run the entire system or raise the context. This expedites the problem-solving process, allowing developers to focus on creating the best possible software. Furthermore, it facilitates better communication between developers. Instead of explaining business requirement nuances or subtle errors, developers can simply say, “Send me the test for this.”

Superior Application and API Design

Good testing practices encourage better application and API design. They help limit the responsibilities of components and reduce unnecessary dependencies (decoupling), leading to more maintainable and scalable software architecture.

Accelerated and Secure Deployments

With robust testing in place, deployments become faster, safer, and can happen more frequently. This is because tests provide assurance that the system is behaving as expected, reducing the risk associated with deployments.

Legacy Projects

In legacy projects, tests enable easy execution of isolated methods. This allows developers to better understand the existing system’s behavior and make changes or fixes more confidently.


In conclusion, software testing is indispensable in the modern software development cycle. It ensures functionality, saves costs, eases changes, and contributes to better project documentation and communication. With software becoming increasingly complex, the need for comprehensive and efficient testing will only continue to grow.