For VCF 4.1 and 4.2 there is no Auto-rotate password feature for every 'X' days for service accounts. This could lead to expiry of accounts.
Service accounts on vCenter Server expires for every 90 days.
operationsmanager.log
root account remediate/rotation fails after resetting root password on ESXi.
2023-06-29T15:29:52.460-0400 INFO [vcf_om,6acb08a361a64915,4adb] [c.v.v.p.r.CancelPasswordTransactionHandler,http-nio-127.0.0.1-7300-exec-9] Cancelling password rotate for entity..{"transactionId":453,"entityName":"XXXXXXX.XXXXXXX.XXXXXXX","entityId":"1b1f75dc-93ce-4bf1-9b1f-c6b51ac0128","oldPassword":"*****","newPassword":"*****","entityType":"ESXI","credentialType":"*****","transactionStatus":"FAILED","transactionTime":"Jun 29, 2023, 3:29:36 PM","updateStage":"TEST_BEFORE_REMEDIATE","workflowId":"f31e2775-92e3-46c3-9d4e-abe8a27f5090","username":"root","diagnosticMessage":"{\"errorCode\":\"PASSWORD_MANAGER_VALIDATE_ESXI_CREDENTIALS_FAILED\",\"arguments\":[\"*****\"],\"errorMessage\":\"(vim.fault.PasswordExpired) {\\n faultCause = null,\\n faultMessage = null\\n}\",\"updateStage\":\"*****\",\"referenceToken\":\"BQDJV6\"}"}