Although this is an organisation issue, not just a project issue, it is important to make sure your team does not send messages to all for something that is specific to one group or one office.
E.g. “A pair of reading glasses have been misplaced. If you have seen these could you please return them to reception.”
This kind of message often gets sent to the whole organisation mail system, which could include thousands of people, when it should be sent just to that local office.
The lost time associated with thousands of people readings a broadly sent email like that and the bandwidth costs could amount to thousands or tens of thousands of dollars.
In the above example, approximately 5000 people received the message. 5000 x 30 seconds is about 42 hours wasted time ($5000+ in billable time). Plus the time wasted in people laughing about it and replying with comments. Plus the storage costs and transmittal costs.
Not only does it make the sender look foolish, it wastes your project time, resources, and if from your project, its reputation.