Explanation:
Experience has demonstrated that reliance purely on preventative controls is dangerous. Preventative controls may not prove to be as strong as anticipated or their effectiveness can deteriorate over time. Evaluating the cost of controls versus the quantum of risk is a valid management concern. However, in a high-risk system a comprehensive control framework is needed, intelligent design should permit additional detective and corrective controls to be established that don’t have high ongoing costs, e.g., automated interrogation of logs to highlight suspicious individual transactions or data patterns. Effective access controls are, in themselves, a positive but, for reasons outlined above, may not sufficiently compensate for other control weaknesses. In this situation the IS auditor needs to be proactive. The IS auditor has a fundamental obligation to point out control weaknesses that give rise to unacceptable risks to the organization and work with management to have these corrected. Reviewing background checks on accounts payable staff does not provide evidence that fraud will not occur.