Texture repeating is because games can only use textures that can only be so big, so they have to tile: that is, imagine bathroom tile, now imagine that your carpet was made from these “tiles” and each tile was the same inch of fabric repeating, these textures are made to have as little unique identifiers as possible so its harder to see when it tiles, but its always visible one way or another; just hidden better, this is because the brain is exceptionally good at finding patterns. Examples: