In most cases, users of financial information would expect a practitioner to provide 100% assurance during the audit or assurance engagement. Issuing such assurance level is not practical due to inherent limitations that are associated with assurance engagements. For this reason, International standards on assurance engagement (ISAE 3000) do not permit a practitioner from issuing a total assurance (absolute) other than the reasonable and limited assurance.
Absolute level of assurance cannot be given due to the inherent limitations associated with the work of the practitioner which includes;
- The use of selective testing.
- The inherent limitation of internal controls.
- The fact that much of the evidence available to the practitioner is persuasive rather than conclusive.
- The use of judgement in gathering and evaluating evidence and forming conclusions based on evidence.