1. logs always fall in one direction - east
2. logs always have the same lenght
3. logs don't despawn
4. logs have no hitbox (otherwise you won't be able to walk through and could easy be blocked (exploitable)
5. logs falling on ridges tend to get stuck, same goes falling on structures like Pallisades
6. buildings that are going to be build have to have a hitbox (i.e. so you can't build a house in a house)
It's up to you to watch where and how you chop - a lot in HnH is trial and error and learning by doing - or study Forums or RoB Wiki (which takes away a bit of the fun)
if you haven't built the stuff in build sign you may take out all stuff and move the log away
sometimes turning on highest run speed enables you to lift something that got stuck
the only way i see to solve this would be that logs always fall to opposite direction of where the chopping char is standing (but i'm sure that will also cause some "log bug" postings

)