The reason is that the quality or material of the product is absolutely not good. The normal contact lens manufacturing process (especially in Korea) has been subjected to very difficult inspection criteria, completing a clean and safe product within an automated manufacturing process. In the process, bad or good products are classified and only the best products are provided to the customer. The loss in the process makes the price slightly higher, but it can maintain good quality. However, cheaper contact lenses from China can be very simple or even non-existent in the inspection process. Usually made of low-cost materials with low oxygen penetration.