It's important to choose a floor tile that can stand up to the daily wear and tear of your household. Scuffs, spilled foods, cleaning supplies, dog scratches, etc. should all be taken into account. Make sure to choose a tile that is specifically formulated for floor use. This natural stone tile shower is a great example, since it has a high COF (coefficient of friction) to keep it from being too slippery. You'll definitely want to do this when choosing a tile for your bathroom floor. Something with a slight raised pattern or texture will increase friction, even when wet.