Greasy skin and coat combined with natural shedding causes matting. And once a small tangle or mat forms, it grows very quickly. The only real defense against tangles and mats is regular bathing and drying done by a professional cat groomer who truly knows what they are doing. Some groomers are not cat groomers and will groom a cat using products and techniques that can cause more problems. Make sure your cat groomer is certified through the National Cat Groomers Institute of America, inc, the only cat grooming association that offers effective, quality training for cat grooming certification.