A laundry's small, but it works hard, constant moisture, a washing machine that vibrates against the wall and a floor that needs to drain properly if a hose ever gets left running. It's easy for a small room to get treated as an afterthought, which is usually where problems start.
Wayne's tiled laundries for 16+ years. Being licensed for waterproofing matters just as much on a small room as a big one, since a leak behind a washing machine causes the same damage either way.