Which factor can compromise the final result of a perm?

Inconsistent rod placement can significantly compromise the final result of a perm because the way the hair is wrapped around the perm rods directly affects the shape and curl pattern. If rods are placed unevenly or at inconsistent angles, the curls will not form uniformly, leading to an unbalanced or uneven appearance in the final hairstyle. Proper rod placement ensures that each section of hair receives equal processing time and exposure to the perm solution, allowing for a predictable and uniform curl structure. This is crucial in achieving the desired look, as any discrepancies in rod placement can result in a poorly executed perm that may not meet the client's expectations.