The one left out will go in a tree. In the 1% of chance he doesn't, he will learn his lesson. Generally they will not remain on the ground unless it gets dark too quick for them to see to fly or they are brooding. My guineas wait until the last minute to go in the coop so I have to wait until it's just about dark to shut the door, so I can understand that that's hard for some people. Right now I don't work so it's okay but I may be in the same boat before long.
