In which case would a non-destructive testing method be preferred?

A non-destructive testing method is preferred when evaluating existing installations without damage because this type of testing allows for the assessment of the integrity and performance of anchors or other structural components without causing any harm or alteration to the structures being tested. Non-destructive techniques ensure that the existing installations maintain their functionality and usability while still obtaining critical data about their condition.

In contrast, minimizing costs might not be the primary concern in situations where the integrity of an installation is crucial, and faster results would not be favored if more in-depth evaluation is necessary. Moreover, testing new materials often involves destructive methods to determine their properties and performance under load, making non-destructive testing less relevant in these cases.