Namely, catching the rare fish for Thousand Cast-Theda/Zona Seeker and opening treasure chests for Agrippa/Pale Rider. It's well-documented at this point that even if the respawn timer on both hunts is done, they won't necessarily appear even if the condition is met.

I've seriously caught almost 10 fish and have gone through half a dozen chests with no spawns (Which is particularly ridiculous considering the RNG involved just in getting a map for the right zone).

It was silly even when the hunts were more relevant, but it's even worse now when hardly anyone wants to bother fishing or buying the maps. It's still worse when there's a chance the hunts may have been killed without anyone's knowledge.