Why won't my chickens use their roosting bar

[ShanandGem]

My Orpingtons still sleep on the floor, but they didn't have strong legs and feet (I have since fixed that with lots of free ranging) and I don't think they felt confident balancing on a bar or climbing.

 

[Jami F]

Have a new built roost with several levels and they go for the shelves on the back wall!!