Minecraft wiki entry for Making_nice_floors, associated text: If a player is planning on staying in a certain house for a long time, they probably want it to look nice. Having nice floors can help with the appearance of a house greatly. Additionally, floors can give players a certain "feel" to the house; for example, using different colors of wool may make them think of the house as happy and colorful, while a mix on nether bricks, diorite, and netherrack with fire on it may make give them a sinister and foreboding feeling of the house.