@Anon the whole point is to strategically make them all suffer in unimaginable ways if they are guilty of being garbage beings. that was said at the beginning of the manga. Light has also said that he doesn't know if there are any other beings as powerful as him and his allies so moving recklessly with zero info on the outside world for the past 2-3 years he spent in the Abyss is the most idiotic thing possible.