Like the title says. Far too often do I send a message, and not have a reference as to what I said because I forget to check the "Save a copy in my sent items" box (unless I ask for them to quote the message back to me).
Not sure if they don't save on purpose due to a technical issue, but it really help if this was a thing.
Thanks for reading.
Oops. What about checking the default button by default instead?