Cartridge brass is a specific brass alloy that has a fairly complex set of grain structure stages. These grain structures are established through various amounts of forming and heat treatments.
The primary cause of case failure is incorrect setup of the resizing dies which results in grain structures that are altered by the forming process. Heat treatment (annealing) does very little to correct these forming errors and is generally of little value to brass that is managed to fit a particular chamber.
The two keys are 1) dies that fit the chamber very well, and 2) carefully setting those dies to move the brass no more than 1 to 3 thousandths of an inch (.001-.003"). Even a few cycles of .005" of forming movement (i.e. resizing) starts to alter the brass grain structure in a way that all the typical annealing methods (torch or electronic) do not repair.
A common error is following the standard manufacture directions for die setup -- "turn the die down to the shellholder, then back off 1/4 turn". Due to all the stacked tolerances in shellholder, die, press, chamber, and cartridge measurements this can result in resizing the brass anywhere from 0 to .015" or more. Missing that .001-.003" window through even two firings will often shorten brass life to 5-10 firings total even with annealing. On the other hand, I have brass that has been fired 200+ times and has never been annealed - always full-length sized to just push the shoulder back 1-1/2 thou.
Another common culprit is the standard resizing die that crunches down the neck, then pulls an expander ball back through it to set the diameter. These two actions usually both violate the .001-.003" movement rule and double up on the forming actions. Switching to bushing style dies and having the small selection of bushings necessary to just pinch the necks enough is a much better investment than an annealing machine.
Annealing has a place. If you are re-forming brass from unknown chambers, or reloading to standard specifications for use in multiple guns, then it makes sense to relieve as much pre-existing grain structure as the annealing process can do. In effect this is what manufacturers are doing through the multiple annealing steps in the manufacturing process.