Final answer:
Before evaluating the success of wet cleaning on masonry surfaces, the surfaces should be properly assessed and documented to establish a condition baseline and identify potential damage risks.
Step-by-step explanation:
Before evaluating the success of wet cleaning procedures on masonry surfaces, the surfaces should be properly assessed and documented. This involves examining the masonry to understand its condition, identifying any materials or elements that could be damaged by wet cleaning, and establishing a clear baseline for comparison. It is important to have this information so that the effects of the cleaning process can be accurately judged. After cleaning, a period of time should be allowed to pass to let the masonry fully dry and to observe any delayed effects the cleaning might have had.