They might be useful and usable, for some people. In a common situation.
They are barriers.
Note: Kit lens 18-55mm, ISO 100, f/20, FS 5.3, resized, no other digital-post-processing.
Key is usable to protect the house. Actually, they could be a problem too. Imagine an earthquake is happened. In special condition, keys and doors are not accessible for the other people.