The answer to 'why is my window filthy' is that there are several common causes, including dust, dirt, and grime buildup, water spots, and residue from cleaning products. Windows can become dirty over time due to environmental factors like pollen, rain, and wind, as well as from daily use and activity inside the home.
Symptoms of dirty windows include reduced visibility, a cloudy or hazy appearance, and noticeable streaks or smudges. To solve this problem, you'll need to thoroughly clean the windows using the right techniques and products. In many cases, this can be done as a DIY project, but for hard-to-reach or extensively dirty windows, it may be best to hire a professional window cleaning service.