A training video to explain the dangers of using personal accounts for tools, such as a Gmail.com email for work, despite having access to a work-provided email, is dangerous, and the risk it includes, such as data leaks, lack of visibility, insurance and compliance violations, and more. This coudl cover the risk of personal email, personal remote access, personal file sharing, etc.

While I know I should/could be preventing the use of personal accounts on work assets, directing my clients away from BYOD use, and restricting cloud tool access to specific devices/IPs - the bottom line is some clients wont implement the tooling, and some co managed clients use us only for training, so we have no choice but to let them us personal accoutns despite the risks.