I run a website where users authenticate using email and password. Some users would like to have two or three accounts using the same email address. I see the use case in their situation, and am trying to figure out which drawbacks it has.
As for authenticating I don't see them: basically it's a query where both email and password are variables. So that would work.
Password reset in case of loss would not work, as email is the only variable in that case. As admins can manually reset passwords, that would be acceptable.
Is there anything I'm overlooking?