The answer to 'why is my countertop stained' is that countertops can become stained for a variety of reasons, such as spills, heat damage, or improper cleaning. Stains can be caused by acidic foods and liquids, oil-based substances, or even just normal wear and tear over time.
The symptoms of a stained countertop may include discoloration, a dull or hazy appearance, or a rough or uneven surface. The solution will depend on the type of countertop material and the severity of the stain. For minor stains, you may be able to remove them with a DIY cleaning method, but for more stubborn or deep-set stains, you may need to call in a professional cleaning service.