For the purposes of this discussion, corrective action is action undertaken to correct the problems identified in an audit report. However, no sufficiently large organization ever implements a complete corrective action plan because it is impossible; it cannot be done.
Therefore, the most reasonable solution, and the one preferred by the professional auditor, is the 95 Percent Solution.
The 95 Percent Solution effectively resolves all the deficiencies in the audit report. However, any sufficiently large organization will have barriers to communication, undocumented requirements, requirements that are under review, etc. Frequently, these are not communicated throughout the organization. Therefore, any corrective action plan is necessarily incomplete1.
It is only a matter of time before a similar problem is noted elsewhere in the organization. Hence, the necessarily incomplete 95 Percent Solution.