Quick Definition
In security contexts, User Carelessness refers to any action taken by a user for purposes of expedience that has a negative impact on security.
Common examples of user carelessness include, but are not limited to, walking away from or handing off a workstation without logging out of an active session, storing passwords or other security-critical information on publicly visible post-it notes, sharing security credentials with others, and exercising poor password hygiene in general.