Login or usernames can be identical to your display name on the front-end, for example as an author of a blog post. This creates an instant vulnerability as you login name is available to anyone. Set it so that the display name does not correspond with the login name.
From the Security & WordPress categories Don’t share login details
If you share your website’s login details, you lose traceability and what happens when one of those users no longer needs access. Everybody must update their details. Always set up individual users and just give them the access level they need and don't forget not everyone needs admin rights.
