You should never publish posts from your admin account. An alert is displayed, informing the user they're logged in as admin and not to write posts.
Admin Post Reminder checks to see if the current user has the ability to manage (add/edit/delete) users. If so, they are considered an admin and the reminder is displayed.
Some plugins allow for custom user roles. This allows people besides just an admin to manage various parts of a site that are usually not allowed by their WordPress user level.
Admin Post Reminder should still work with these types of plugins. If a user has the ability to manage other users information, they are viewed as an admin user and the message is displayed.
For 2 main reasons:
An admin can create a new post from any page in the backend by using the admin bar and choosing 'New Post'.
Some WordPress plugins provide other places where new posts can be added or edited (Flutter, for example, has the option of writing posts in a custom write panel).
Instead of trying to guess where a user's going to be writing their posts or what other plugins are installed, Admin Post Reminder simply displays an alert on all backend pages.
Possibly. But since this plugin is targeted to security-conscious people, it's always best to use the most recent versions fo WordPress.
To read more about this plugin and why you might want to use it, visit the author's site: