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.
Which means that you'll have a scenario where you have 5 players hovering around an NPC, waiting for him to lose his battle with a local monster. Then all of them immediately pounce on him and revive him. Thanks to the NPC AI, NPCs will instantly run toward any monster in their area, creating a loop of "wait for NPC to die, revive NPC, watch them suicidally run to another enemy, repeat."
It's hilarious to watch, making it the "best" daily. For certain values of "best."
It's also really, really stupid to give players an incentive to allow other players/NPCs to die. Even if it is fun to watch.