Modified bitumen roofing problems often arise from inadequate application techniques during the asphalt or bitumen modification processes. Issues such as poor adhesion, blistering, and premature aging can occur if the modification materials are not properly blended or applied at the correct temperatures. Ensuring uniform distribution and proper curing times is crucial. Additionally, environmental factors and substrate preparation play significant roles in the performance of modified bitumen roofs, necessitating strict adherence to manufacturer guidelines and best practices.