Mandatory auditor rotation is designed to address a potential conflict of interest between a public company and its auditor. Because an auditor is hired and paid by the public company it audits the auditor's desire to maintain a good relationship with its client could conflict with its duty to rigorously question the client's financial statements.
If we survive danger it steels our courage more than anything else.
Anger and hate against one we love steels our hearts but contempt or pity leaves us silent and ashamed.