So, a question for pre-4e DnD players ... what was "attrition" like in those editions?
"Attrition" or Resource Management, has been a big part of
every edition of D&D.
In the classic game (I played/ran Basic, AD&D, & 2e from 1980 to 1995 for context), spells were a major resource, hit points were of obvious importance, too, but via (mostly Cleric) healing, were also limited by spells (natural healing was too slow to matter if any magic healing was available), and there was the odd ability that was times/day, There were plenty of magic items that were consumable or n/day (or turn or hr or week, the classic game was all over the place), but they were very much resources doled out by the DM. There were mundane resources to be tracked & managed - rations, water, light sources, etc - but their cost was trivial out of the lowest levels, and items or spells could obviate them.
So players' management of resources in the classic game was centered on spells, the most powerful/important player resource, hands down.
Because spells were precious, and, at low levels, few, it was not unusual for the Clerics to leave their party a bit wounded from one fight to the next, rather than 'waste' a spell healing fewer hit points than it might have - though, y'know, not everyone agreed with that, but it wasn't as obvious as whack-a-mole healing in 5e.
So there
was often some hit point attrition from one fight to the next.
Hit point attrition from one fight to the next became of minimal importance in 3e thanks to WoCLW (3.5, WoLV) cheaply converting gp to hp, (which, for whatever reasons, didn't trigger Grognards enough to instigate total war against it). After each fight you could take a minute or few to heal everyone up (rounds were already 6 seconds, so even draining a WoCLW entirely - on average 220 hp - only took 5 min Natural healing was still pretty slow, so it was faster to take an extra day and have the Cleric (or other caster who could) just take & cast
all healing spells. Outside of that, casting a healing spell would be reserved for getting someone back up immediately in a tough fight, or saving the gp cost of the wands (and, of course, making more wands)