If you have the rebook reminder pop up after a clients sale, sometimes you click Yes to rebook the appointment, and sometimes you click No.
If you click No and instead build a brand new appointment for the same client later on, this new future appointment is still counted in the rebooking results.
Simple Salon counts all future appointments that a client has as a rebooking, so don't worry if you are not always rebooking appointments via the actual Rebook Reminder, which pops up at the end of a clients sale.
The best report which tracks and records your rebooking figures is the Client Retention Report. Click here to learn how to use this report, it's a really good one.