The answer to 'why is my hardwood floor greasy' is that a greasy or oily film on hardwood floors is usually caused by a buildup of cleaning products, furniture polish, cooking oils, or other residues. This can make the floor feel slippery and appear dull or discolored.
Some common causes of a greasy hardwood floor include using too much cleaning product, improper cleaning techniques, spills or splashes from cooking or other household activities, and the use of furniture polish or other products that leave an oily residue. Over time, this residue can accumulate and create a greasy film on the surface of the floor.