Fewer grout lines matter more in a shower than almost anywhere else in the house, since every joint is a potential entry point for moisture over time. Large format tiles keep that risk to a minimum on both walls and wet room floors, while still giving the space a calm, flowing look rather than a busy grid of small tiles.
Porcelain suits this environment gorgeously thanks to its non-porous surface, and a gloss or polished finish on the walls can make a shower feel considerably more open and reflective than its actual size. Floors are a different matter: an anti-slip finish is essential underfoot, and every tile in this collection carries an appropriate rating for wet conditions. For a bit of character, many people bring in a smaller decorative tile, perhaps a zellige or mosaic design, inside a shower niche alongside the larger format elsewhere.