Why is the price of medical devices not transparent?

Medical devices are not the same as pharmaceuticals, there are many different categories, the efficacy is different, and the materials used by each manufacturer are different, the cost is not the same. For example, the materials used by private companies in general are general materials, assembly line employees are not educated, management and testing equipment is not comprehensive, and not quite in line with national standards, so the price is low. Imported products use certified components of all parts, staff quality is also relatively high, quality is also better, the price is naturally many times higher. Once the price is harmonized, is it to high or low to come. Also, how to calculate the discount to the hospital, to the dean of what the cost of how to calculate?