Tracked changes show what moved. They do not show why. A deleted indemnity sentence and a rewritten notice period can look the same in the margin, even when one is a hard position and the other is a cleanup.
When you send a redline turn, you can include a short message. The note goes with that turn. The other side sees why the draft came back, not only the markup.
The message is optional. A turn with nothing to explain can still be sent as markup alone. When there is a reason, it sits with the turn the other party is about to open, instead of in a separate email that can get lost from the draft.
