As I understand it certain quests are tied to a set amount of long rests. Take to many long rests after you started this quest and this person dies, and so on.
In some cases no rest is even required. Just move away from an area after triggering the initiation of the event and the event will progress automatically (typically to a failure state or at least a less than ideal one).
Which is part of what makes the suggestion in the OP misguided at best and openly awful in certain situations.
