Generally, when I teach Project Management courses in university classrooms, when we touch on the topic of quality, I usually use a resource which is a video I found on YouTube about the cost of quality. Surely the curious reader has already looked for it or seen it on the internet. This video describes three very serious accidents that humanity went through because those who made the decisions wanted to "save money," neglecting actions related to quality control. These situations occurred at NASA, Toyota, and in the United States, causing in some cases very high personal and material losses.
Those of us who work in technology must never lose sight of the ultimate purpose behind the code we develop, the server we configure, the cabling we connect, the UPS we install. The technological infrastructure aims to provide a service to society and to individuals, who expect "the system" to help them when they need it most.
A data center is the central part of this technological ecosystem, so ensuring its proper operation and covering any contingency scenario is vital for an organization that is dedicated to its customers.
It is true that in my professional career I have encountered several people at different organizational levels who do not share this same vision. I remember when we were working on local network implementation projects at a company, there were clients who wanted us to forgo certifying their cabling, believing that continuity testing would suffice. Similarly, in electrical installations, they felt it wasn't necessary to perform all the protocols, even in mission-critical infrastructure. I recall that a biased view of value to the organization failed to acknowledge the costs of quality, which experience and best practices recommend. It's better to prevent problems than to regret subsequent rework or losses, as in the case of the video I mentioned earlier.
The certification process, carried out by a third party, will reveal hidden flaws in the design or implementation, as well as test and verify the functionality of the equipment and systems of a Data Center. Each company should make its best effort to select how and where to carry out this process, but it is the only way to validate whether your company's Data Center meets the requirements for which it was designed and built.