Centering a shower valve right under the shower head is standard procedure. The shower valve is the piece with the handle where you turn the water on.
Relocating a Shower Valve
But at All About Bathrooms, we sometimes like to offset the valve to one side, especially if you have a handheld shower head. That way, the hose from the shower head won’t get caught on the handles or get in your way when you’re adjusting the temperature.
This might require moving or boring through a stud to do an offset installation, but that’s a small hassle that pays off in the long run.