Guild Wars 2 recently introduced "rotating dailies" so that the "daily" tasks you need to do change every day. One of the daily tasks in the rotation is "Daily Healer" which tasks you with reviving 10 people, which can be either other players or NPCs.
Reviving 10 players is next to impossible unless you play with really, really bad players who die frequently. So most players just opt to revive NPCs instead.