My Barred Rocks give me an egg a day without fail. So do my Partridge Rocks, Columbian and Silver Laced Wyandottes and Blue Andalusians. Maybe it is a competition thing with my girls. 20 hens = 18 eggs each day so someone is slacking but they probably deserve a day off now and then.Barred Rocks are known for their evil ways. They will never lay!
In seriousness, if they are from a hatchery, expect an egg any day. I think all of my hens began by 18 weeks except the Heritage Marans. They were 22 weeks.