In the recent past, unskilled employees/contractors are using proxies to help in their work by allowing them to remotely connect and operate their machines, unknowingly exposing company confidential information along with violation of organization policies. 

There are certain types of malwares (zero days) before getting detected by antiviruses, they are capturing confidential information from user systems and transmit to the attackers. 

Unknowingly employees while sharing their computers have been exposing restricted/confidential information to unintended users, resulting in data leakage and loss that can be prevented. 

When outsourcing certain business-critical functions, we tend to provide access to certain systems including user systems for support. However, when sometimes, with or without user acknowledgment, a support system can see the running applications and data within.

When an internal employee/contractor who is a employed as a bug in organization by state actors or competing organizations, they use certain data loss prevention tool evading mechanisms by screenshoting the specific content, change file type and share - or by screensharing certain content for fraction of seconds to unknown actors 

When certain content is being operated or stored in user machines and that data can be leaked intentionally or unintentionally by a user by screenshoting, screen recording, screensharing etc which cannot be stopped by existing DLP, Data Protection tools.