In all my experience playing DnD, every DM I've had would stop attacking a character immediately upon them falling to zero hit points. Now, that makes a lot of sense from the monsters' perspective. The character is no longer a threat, so they should move on to other threats. However, I've also yet to have anyone die of three failed death saves. In almost every case, the battle is over before the downed character has taken three turns. And all this makes total sense, because until the party gets access to spells that can bring party members back from the dead, any party member death usually either means the DM has to handwave some reason for an NPC to revive them, or that player has to scrap their character and build a new one. But as soon as one party member gets access to the spell revivify, that dynamic changes. Now a player death is no longer a huge disaster, it's merely a drain on the party resources. I'm curious, then, as to how many DMs will start being willing to kill off characters after the party has access to a spell to bring them back, and how they contextualize that in play where previously the enemies would ignore unconscious party members. Or, if they are willing to kill of party members before the party gets access to this spell, what happens to the characters who get killed?