I keep count for maintenance purposes, selling or trading down the road, and should it need to go back for repairs for a particular reason I can give an accurate figure on how many rounds I've run through it.
I also keep a break down on what kind and how many rds of different ammo I've used. To try and watch for trends of any kind that a particular pistol may or may have with different types of ammo.
NRA Certified Pistol Instructor, Home Firearm Safety Instructor, & RSO
On the range again, just can't wait to get on the range again. The life I love is shooting guns with my friends, and I can't wait to get on the range again!