Moisture is the first thing to rule out
Showering is one of the sources of excess indoor moisture that Sherwin-Williams links to interior peeling, and it says bathrooms with showers should have exhaust fans. Its general peeling guidance also lists leaks in roofs or walls and worn or missing caulk at joints, so a bathroom location doesn't prove steam is the only cause. The water source should be found and fixed before anyone repaints.
Note where the peeling starts and whether it gets worse after showers or wet weather, and share that with the painter. If the fan runs but the room stays wet, our guide to a bathroom fan that doesn't clear condensation covers what to check, and our guide to cracked grout and failing caulk explains why a joint can let water behind a finish. A suspected leak inside a wall or roof should go to someone qualified to investigate it.
Preparation matters more than another coat
A fresh coat over a dirty, wet or glossy surface, or over paint that is already losing its grip, doesn't fix the underlying problem. Sherwin-Williams says to remove peeling paint, clean and prime the surface, follow the product label and data page for preparation, and test the remaining paint in a 6 to 12 inch radius around peeled areas to make sure it is still well attached.
Ask the painter how they'll check adhesion beyond the visible edge, which layers they expect to remove, and which primer and topcoat they plan to use on that surface.
Latex paint isn't automatically the problem
Sherwin-Williams' interior product FAQ says latex eggshell and semi-gloss coatings work well in a bathroom as long as there is good ventilation, and that damp walls from poor ventilation can lead to peeling. Switching paint types without fixing the moisture isn't a complete repair. If the existing paint is glossy, ask what preparation and primer the new paint needs to stick to it.
Mold and older paint come first
EPA's guide to mold and moisture says not to paint or caulk moldy surfaces, to clean up the mold and dry the surfaces before painting, and that paint applied over moldy surfaces is likely to peel.
If your home in Northeast Philadelphia, Bucks County or elsewhere was built before 1978, it may have lead-based paint. EPA's lead-safe renovation page warns that renovation, repair and painting in pre-1978 homes can create dangerous lead dust, recommends hiring a lead-safe certified contractor, and notes that contractors doing that work in pre-1978 homes are required to be certified. Settle that before anyone scrapes or sands.
What a good repair quote covers
Ask for a written scope that separates fixing the moisture source, removing failed paint, surface repair, cleaning, priming and finish coats, and says what happens if wider peeling turns up. Our guide to blistering exterior trim paint covers a related moisture problem outside, and our contractor hiring checklist lists questions to ask before you sign.