I did a large raw material zone in an underground place where i also have an iron mine. Placed the zone in 1 time covering the shaft and people tries to drop stuff there and gets stuck in a loop, trying to place stuff where the shaft is, dropping in a near place out of the zone, then try again and so on...
Fixed the zone manually but well, the game shouldn't let me place the zone like that since i noticed it kinda late and they were wasting time hauling in that loop.

