My guess is that they picked the bottom and side tile, and didn’t realize that large tiles are a pain in the ass on curved surfaces. They require a lot of time to cut and mortar. Sheets of penny tiles are already cut into something that can flex on a curve.
But sane people usually continue the penny tile up one of the flat sides so you don’t have a hodgepodge of different stuff.
Oh, it’s inside a pool! Yes, the nearly horizontal surfaces are the border tile, the transition tile and the pool bottom tile.
It does make sense. But I’m not sure why one would want 3 different tiles in a pool (the vertical, transition, and bottom).
My guess is that they picked the bottom and side tile, and didn’t realize that large tiles are a pain in the ass on curved surfaces. They require a lot of time to cut and mortar. Sheets of penny tiles are already cut into something that can flex on a curve.
But sane people usually continue the penny tile up one of the flat sides so you don’t have a hodgepodge of different stuff.