The answer to 'shingles water stains' is that they are typically caused by leaks or moisture buildup under the roofing shingles. Common symptoms include discoloration, staining, or mold growth on the shingles or in the attic. Solutions may involve replacing damaged shingles, improving attic ventilation, or addressing underlying roof leaks.
Homeowners can sometimes DIY minor shingle repairs or cleaning, but more extensive water damage or roof leaks usually require a professional roofer to properly diagnose and fix the issue. Trying to DIY complex roof repairs can be dangerous and may lead to further damage if not done correctly.