It's a 10 for me because I can never remember on my own. I keep detailed logs and add reminders to my calendar to help me keep up with it. Keeping accurate logs can also boost resale value, though that's not my primary motivation.
Keeping detailed maintenance logs on my equipment is tops for me too. It's just like keeping detailed information on my truck, car, ATV, furnace, etc.. How will you know when it needs maintenance if you aren't tracking it?