Capital One has added a feature which allows a unique login for a special type of authorized user who has the elevated status of ‘account manager’. The account manager can create a login to manage the account, review transactions, make payments and the like.
Typically we just share the login info with someone who we trust with the account. But this still can be a useful feature in some situations.
I believe many banks (e.g. Chase, Amex, etc) have a feature to appoint an account manager who can manage the account, even to close it out, over the phone.
Hat tip to Maybe Frugal