All the time when we clean furniture we pull all kinds of gunk out. Things like sweat, body oils, drool, food, beverages, dead skin, hair, pet dander, and stuff we would rather not think about, let alone put in your head. This is the stuff on a professional furniture cleaner can get out.
The thing is, upholstery fabrics are designed to hide this soil. But don’t kid yourself. Most people will spend 4-8 hours a day in their favourite seat. About as much time they spend sleeping. How often do you wash your bedding? How often do you wash your upholstery?
Vacuuming does help. It removes a lot of the dry soil from your fabrics, but to safely and effectively remove the bonded soils I mentioned above, you need specialized equipment, and cleaning agents to get the job done.