1. Customers
   1. Overcharging
   2. Limited Product Using Knowledge
   3. Using Product after informing about Product Hazard
2. Manufactorers
   1. Bad Quality Control
   2. Mistaken Production Processes
3. Products
   1. Understandard Products
   2. Materials of Product
4. The Company's Policy
   1. Uncovered Problems
   2. Unaccesed Information Distribution