I try to keep up with the number of times fired. I keep fairly good track of rifle brass and it isn’t too hard since it’s usually in smaller batches anyway.
With high volume handgun rounds I am much less diligent. The revolver brass life span seems more dependent on how much you flare the mouth and the auto stuff usually gets lost before it gets old. For that reason the only time I insist on using newer brass for handguns is for max loads on magnums. I feel better with, at most, twice fired brass for those loads.
The one weird situation for me is 223 brass. I load a fair amount of it so it isn’t possible to keep track of all of it. I keep good records on batches that are used for target loads and the high volume plinkers with GI surplus brass are only loosely accounted for. Since brass is so cheap and plentiful I just discard any doubtful ones when inspecting.