Insider Threat Awareness Training for Employees
A systems administrator at a defense contractor copies classified schematics to a personal USB drive over the course of three months. His badge still works. His credentials are valid. He passes the same security checks as everyone else. Nothing in the firewall logs, intrusion detection system, or email gateway catches a thing.
When the breach is finally discovered, it is not because a tool flagged it. A coworker noticed he was accessing project folders he had no business being in and mentioned it to their manager. That conversation, uncomfortable as it was, prevented months of additional exfiltration.
External attackers need to break in. Insiders are already inside.