The effectiveness of a control refers to how well it achieves its intended purpose of reducing the risk of material misstatement or error in a process or activity2. One way to measure the effectiveness of a control is to monitor the number of control deviations detected, which are instances where the control fails to operate as designed or is not applied consistently or correctly3. A high number of control deviations indicates a low effectiveness of the control, while a low number of control deviations indicates a high effectiveness of the control. The other options are not good indicators of the effectiveness of a control, as they do not directly relate to the performance or outcome of the control. The scope of the control coverage, the number of exceptions granted, and the number of steps necessary to operate the process are more relevant to the design or efficiency of the control, not its effectiveness