Mine have had chickes in a top nest box. Mine are dog cages from a shelter stacked so it has a door. The problem I had was an early hatch would go on a walkabout and not be able to get back. So I shut the door when it's lockdown and open when she is done.The nesting boxes are too high off the ground for chicks to get in and out for food.
Most of the time my hens use a different box after they hatch, even when I cleaned it out. I figure it's to prevent predators from finding them, hatching is a messy business.