Bert, I think this may have something to do with how much you can depend on your staff. If I send a message to a staff member, I have to assume that 1.they do it, and 2.they document it by sending a message back to me so I can save it to the chart.
If the staff member doesn't do this, I have no record of having asked, and my feeble mind will likely forget it. At least if I can message the staff and save the message, I know I did my part in making the request and my intent was documented.