The tiles are glued to a piece of plywood. I tried to get one tile off, but I cracked it. This is a job that requires a delicate touch, lots of patience and a large dose of luck. It is possible to remove ceramic tile from some surfaces, but in certain cases you can indeed waste vast amounts of time. The fact that the tile was glued directly to a wood substrate is a good sign.
Ceramic tile is a brittle material.
In many respects it resembles concrete. Both have high compressive strength. This means you can squeeze or compress them, and they often will not break. Bending or twisting a material subjects it to tension. The first thing that needs to be done to even have the slightest chance of success is to remove the grout between each tile.