Generally, chickens will try to roost at the highest point they can get to in the coop. So, if there is a place available in your coop that is higher than the roost you built, they will prefer the higher place. And it's hard to tell from the pic, but the actual poles that the chickens' feet would be on look small to me. I use a 2 x 4 with the broad side up.
K. The poles between the ladder pieces? One is a shovel handle, the others rake handles. I was "re-purposing". Yup, probably need to be bigger. Thanks!