Why is it important to review the market for new suppliers, or options, to fulfill a procurement need

Why is it important to review the market for new suppliers, or options, to fulfill a procurement need? What role does legal and regulatory compliance play in procurement? What criteria are used to evaluate bids? How are these criteria defined?
Why is it important to review the market for new suppliers, or options, to fulfill a procurement need? What role does legal and regulatory compliance play in procurement? What criteria are used to evaluate bids? How are these criteria defined?