Both… functional art.
The original problem is that there was a water shut-off valve for the whole floor in the shower. Very ugly to have a valve in the corner on the floor and somewhat in the path of the shower. Handle was rusting. It was embedded in a solid block of concrete with the handle sticking out. The valve started to fail (did not completely shut off the water). And it was the kind of valve where the whole valve needed to be replaced. Terrible work by the builders. I had to demolish the concrete to reach the valve.
So I replaced the valve with the kind of valve that has a replaceable cartridge. But I also refused to embed it in concrete again. I will build a removable box around it. But the box could not be waterproof and also easily removable on the fly whenever the valve needs to be accessed. So I put a hole in the wall (shower to bedroom). Then I attached a 90° gearbox drill accessory and a shaft to that goes through the wall. On the bedroom side, I could have just put a handle. But I found a wood helm to a ship, but miniaturized. I thought that would be the perfect steampunkish valve handle. But it did not clear the wall. So i got carried away and put a bicycle sprocket on the shaft, and mounted the helm to another sprocket, which i attached to the wall higher up. And wrapped a chain between them.