I look mine over after firing, as the black powder residue makes it easy to see any cracks, and then again after polishing. I tried the counting method and was too much of a pain. I ended up with 50 pcs of 3 reloads, 150 pcs of 5 reloads, etc. I watch for stress cracks at the mouth of the case, splits down the side wall, bulges at the bottom. Some brands of brass are better than others. I will never buy Starline brass again. I got 3, maybe 4 reloads out of them before having a huge amount of case splits. Cheap brass doesn't always mean it's cheaper to use. I've had my best luck with Remington and Winchester brass.
There are three kinds of men:
1) The ones that learn by reading.
2) The few who learn by observation.
3) The rest of them have to pee on the electric fence and find out for themselves..........