If you have configured a “request and approval” work flow for an account, some users might have temporary Login or Checkout permissions. If a request for login or password checkout has been temporarily approved, the permission will have an expiration date and time. Active sessions can continue past the expiration, but users will not be allowed to log on or check out a password without submitting a new request for access.
Only users who have requested and been granted temporary access by a designated approver display an expiration. The Expires column is blank for users who are explicitly granted a permission outside of the “request and approval” work flow or granted a permanent permission by a designated approver.