The answer to 'why is my upholstery stained' is that there are several common causes, including spills, pet accidents, and general wear and tear. Symptoms can include visible stains, discoloration, or a dull appearance. The good news is that many upholstery stains can be treated with the right cleaning methods, but the approach will depend on the type of stain and the material of the upholstery.
For small, fresh stains, you may be able to tackle the problem with some DIY spot cleaning. However, for larger or set-in stains, or if you're unsure about the best cleaning method for your upholstery, it's generally best to call in a professional cleaning service. They have the expertise and specialized equipment to safely and effectively clean your upholstery without causing further damage.