If you think about it most if not all companies are working hard to meet sometimes unreasonable customer demands. The very same companies turn around and make unreasonable demands on their own suppliers. Many, many problems in the supply chain are directly related to the company not communicating to the supplier what their needs and priorities are.
The question arises why do companies continue to treat their suppliers as second class citizens. Suppliers are there to help you problem solve if you just let them. The answer lies in a failure of management to recognize it is more effective to direct purchasing work with suppliers rather to brow beat and punish suppliers. Issues that arise in the supply chain are opportunities for learning and growth for company and supplier resulting in a strong long term problem solving relationship.
Is your supply chain a constant struggle? Why not let your supplier help you fix it? Does your company have an it's always the suppliers fault attitidue?