There are a small handful of quests that are time-based, and in some cases they seem to have faulty triggers. As many people have noted, if you take your time talking to Ahriman the first time you enter the starting city, the nearby burning boat will sink. This happens even if it hasn't been revealed yet (ie, still covered by the Fog of War), and you have no way of knowing that there's a burning boat nearby.
Given the lack of a pause function, the time-based quests are a bit of an annoyance. Thankfully, they're few and far between.