Settlers who are building go to the house that is being built, take wood off. then go back to stockpiles and drop the wood and then pick up the same piece e of wood right away (instantly after the drop animation) and walk back to the house being built to build with that wood.
Villagers also will go to a stockpile to put down wood, drop it, pick it up and put it back down again and walk off.
seems to be an AI bug.
It is pretty easy to reproduce, build a house while chopping trees
Excpected, villagers build house by going to stockpile to grab wood and heading to the house. If they are removing wood from a house they should remove it then bring to a stockpile and walk away.
If the villager is chopping they should bring the wood to the stockpile, and walk away or directly bring the wood from the tree to the house that is under construction.
Villagers will go to the house, take wood off of it, bring it back to the stockpile, then pick the same piece up again, then head back to the house to build.
Also, villagers will sometimes decide (when bringing wood back from chopping) to drop their wood at the stockpile, then pick the same piece of wood back up, then drop it in the stockpile (again).
It is: Minor
Yes I am running r34,