Which of the following best describes the purpose of non-functional testing?

A disadvantage of independent testing is that developers might lose a sense of responsibility for the quality of their work. When developers rely too much on independent testers to find defects, they may become less diligent in their own testing and quality assurance efforts. The ISTQB CTFL Syllabus points out that while independent testing can provide an unbiased perspective and identify defects that might be missed by developers, it can also lead to potential downsides such as diminished developer accountability​​.