Extending that analogy, I enjoy having a robot that will tell me if all the enemies are dead. Then I can try out different spells to my heart's content without having that nagging doubt about their effectiveness.
Except it's not a robot. It's a robot per body. Sure some components are common but you still have to build and grease each bugger yourself and adjust them whenever you change the spell in any meaningful way because enemies will drop differently. I'm too lazy for that. I'll just walk with the people I should get through the room and kill the enemies that are meaningfully not dead. Besisdes, after this room, there's another and who has the time.
From time to time some of the people I lead will die due to my sloppiness but such is life. It's not like I'm leading royal family through this dungeon.