My big girls would only use the ramps to go up. Even now, my Cochin, doesn't like to be up high. I put her on the roost every night. If I don't, she roosts on the edge of the poop board, and I'm worried she'll get piop on her. She is 100% white and, like, 150% feather. I hate to think of getting poop out of all those fluffy white feathers. LolI actually added the ramps the first day my new adult flock flew into the mesh walls.
That was just new environment, but it freaked me out.
Most the birds jump down from roost/board, but the big ones use the ramp.
My bedding is also not so deep(0 to 2-4"), sometimes the bare floor is exposed, but they jump on it anyway.