If we visualize this approach as a left-to-right line, with development start on the left and production release on the right, testing was only done at the right end of the line, at the end of the software development life cycle. This generated delays in the delivery of projects due to the need to correct errors or usability problems.
In recent years, in connection with the adoption of agile development practices, the concept of “shift left testing” has emerged. This approach seeks to find and prevent defects early in the development process, focusing on quality from the very beginning of software construction.
A 2017 study found that detecting vulnerabilities early in development cost about $80 to fix, while fixing those same flaws after going into production could cost about $7,600. This shows that the cost of detecting and fixing defects in software increases exponentially as it progresses in the development life cycle, due to the greater impact and need for more additional work at later stages.
Benefits of adopting the “shift left testing” approach in agile development.
The “shift left” strategy involves testing as early as possible and often, and test automation plays a key role in this approach. In addition to the cost benefits mentioned above, this shift to the left in testing processes also offers other benefits, such as improved code and software quality, increased speed of delivery by quickly fixing defects and avoiding costly delays, and increased ability to automate testing, reducing human error and expanding test coverage.
In addition, in tests it is aligned with the general agile development strategy, providing speed and efficiency. Involving QA analysts early in the development cycle enables them to understand requirements, software design, architecture, coding, and functionality, enabling them to seek clarification, provide feedback, and design scenarios that help identify defects even before coding.
Finally, the “shift left testing” approach promotes greater participation of all interested parties, which facilitates a clear understanding of the fundamental objectives of the software. This allows more complete tests to be designed and encourages teamwork, where quality is the responsibility of everyone, from testers to developers, business analysts, production support staff and managers, among other collaborators.