So true. A chicken doesn't know that coop is home until it has been forced to sleep in there for several nights.
Until then, they are just as content sleeping on the bed of a pickup truck or a porch handrail. No one ever told them what a coop looks like.
And remember that once you FORCE them to inhabit your coop they still may prefer to roost in the weeds.
Take your chances. Chickens who roost in the sticks are gambling men who IMHO would rather take the chance of a GHO eating them instead of Red Roost Mites doing it.
I think it is trial and error until you find a combination that works for your girls. The right kind of roost bar and height, the right lighting, ventilation, bedding, nesting box, feed, temp, etc. The list could go on for days. However you decide to deduce what the problem is, the #1 priority is to keep your girls safe. I think that is something we can all agree on 