Like financial audits system audits are not conducted on sampling basis. Because each and every system is important and results of few sample systems could not be generalized to whole network. The reason behind this approach is the fact that hackers or intruders tries to explore the weakest link in enterprise security. That weakest link could be any system on the network. Therefore it becomes essential for auditors to conduct a full fledge system audit, identify the weakest link in enterprise security and fix them.