I sent 14 villagers to build a mill at deer near a stealth forest on High View. They finished the mill, but instead of hunting deer they just stood around, not working but not showing as idle either.
Over 13 minutes later (!!!), I tell them to build farms, however they remain in this state instead of building the farms. I think I shift-clicked to build the farms, and in the video where I have one villager selected you can see the blue line starting at the mill and connecting the farms. So my guess is that for whatever reason the villagers don’t think they’ve finished constructing the mill yet, and are waiting for that to happen before starting their next command (hunting deer, building farms, or properly going idle).