Have an option that if an athlete walks away or just disconnects from a coach the last 3-6 months' worth of programming gets deleted too? Not the data so what they did would still be there but the workouts that the coaches have spent time creating. So easy for someone to just leave and then go to another coach who potentially has access to all your workouts. On the flip side of that if a coach removes an athlete then there is the option for these to be deleted or not.
As coaches, we spend a good bit of money on training peaks as software and our own time creating workouts but it's so easy for these sessions to just be copied elsewhere when athletes leave and go with someone else.