For rifle brass, fired brass goes into a ziploc bag with a note inside that says "X-Times Fired".
Pistol brass is fired until it splits.
I put a bar-code on each piece of brass and scan it with a handheld scanner which uploads to my Smart Phone.
Available at Sinclair/Brownells.
Till they fail. This is normally due to loose primer pockets. My brass processing includes a annealing cycle for all rifle brass. Have never had a case head separation, been doing this for over 40 yrs now. School of old knocks, learn to setup your dies correctly and the brass will last a very long time. My Lapula 223R brass has over 10 cycles on it and the primer pockets are where only the #41 have enough tension to hold the primer. 1 more firing and they will all be scraped.So the follow up ? For those who keep track, what's the magic number to throw them away?