[blincoln]

If one does any of the following and wants to keep track of it in a structured way, it might require custom fields in some password managers:

* Use a different name for each account * Use different "personal information" (date of birth, etc.) for every account * Track "security" questions and randomly-generated answers for each account, for services that still use that terrible approach * Track which phone number is associated with each account, for services that uses SMS MFA codes * Attach list of one-time recovery codes to accounts that use those * Attach source of credential information when credentials were sent by someone else for e.g. testing

There's six reasons off the top of my head. I'm sure there are more.