What causes cracks in leather seats, and can they be repaired?

Cracks usually start in the protective topcoat on high-wear areas such as side bolsters, caused by friction, flexing, heat, UV and dirt acting as an abrasive. Regular cleaning and protection slow the process. Once the topcoat or leather has cracked, cleaning products cannot reverse it. Small cracks can often be repaired with filler and color-matched leather dye, while severe damage may need professional repair or panel replacement.