Briefly describe why on most audit engagements an auditor tests only a sample of the transactions that occurred

On most audits, it is not feasible or cost-effective to audit all transactions. For example, in a small business, the auditor might be able to examine all transactions that occurred during the period. However, it is unlikely that the owner of the business could afford to pay for such an extensive audit. For a large organization, the sheer volume of transactions prevents the auditor from examining every transaction. Thus, there is a trade-off between the exactness or precision of the audit and its cost.