Supplier Motto: Have deliverables with best of Quality in competitive lead time.
Buyer Motto: Meet the Client expectation with superior Quality of Product and service.
If looked at these 2 motto they are just the same. So where exactly the problem is may be the supplier control? You give the specifics to the subcontractor or supplier of service/product, timeline needs, price ranges, and quality expectations. But still there are problems in supplier supply chain then there is lack of supplier control.
A close attention needs to be paid at the process as well evaluating the steps taken to select supplier and their deliverables. Purchasing process in most of companies is entrusted to an individual who has an access to various distributor networks who partner up with manufacturers as well as service providers to provide the end result. Supplier selection is based on price, quality and ability to meet the demands of the organization.
One parameter of selection to be included to this structure of short listing should be evaluating supplier and performing Risk assessment to supplier control. It is not a requirement of just quality system but also the cost of doing business.
Depending on the Business model this criteria can be enforced to supplier control. If supplied products and services form the backbone of your Business stiff considerations and controls need to be in place. If supplied products /services are part of your offering which does not affect the quality of product or service offered then moderate control needs to be exercised.
Just keeping information of selection and evaluation is good practice with supplier control. In case of stiffer controls, Supplier Risk Assessment, Supplier Contracts (Specific to Product/Service) along with alternate supplier list all help maintain the subcontracted supplier process in check.
Review your internal process and check if your needs can fulfilled with following checklist:
1) supplier control
2) Supplier Evaluation
3) Supplier Risk Assessment
4) Supplier Corrective Action Requirements.
Periodic evaluations will reveal the glitches in purchasing process and will provide the necessary tools to make a advised decision if your organization needs more control or not.