My guess is that you probably haven't tended a wood fire or collected firewood. That means they are also the most important ones to gather in collecting a load of firewood. Sometimes, it does include things that take a bit longer, like adding Post Offices from a GNIS search for one county. That factor alone leads to the question of which projects get priority. Requests come first.
Demand comes next.
When I have no pending requests, the hit-counters rule and the section with the most hits usually goes to the top of the list. The exception is when another section is nearing completion and I really want the satisfaction of marking it off my list.