Bath work starts as a complete redesign when the layout no longer fits the house. That can be a new shower, a reworked vanity wall, or a room that needs to be easier to use.
Shower design is called out on its own: comfort, a walk-in shower, or a walk-in tub when stepping over a traditional rim is the problem.
The surrounding finishes, paint, and cabinetry can be built with the same job so the bath does not look added on.