Apartment doors, walls and floors can withstand many hours of continuous burn. The building would never be on fire, at worst you’d have one apartment or one floors public areas on fire before it’s put out. If my apartment was on fire, no alarms would sound in the building, only within my apartment, it doesn’t matter to my neighbours.
There’s certainly scenarios in which you might need to evacuate, like a bomb threat, but we are speaking about internal fire, in which case there’s more danger in hundreds of people fleeing in panic down stairs (whether that’s 1 stair case or 2) than staying inside.
There’s certainly scenarios in which you might need to evacuate, like a bomb threat, but we are speaking about internal fire, in which case there’s more danger in hundreds of people fleeing in panic down stairs (whether that’s 1 stair case or 2) than staying inside.