Final answer:
The success of JIT (Just-In-Time) relies heavily on having strong communication and reliable suppliers to ensure timely and consistent delivery of parts, which reduces inventory costs and improves quality control.
Step-by-step explanation:
Concerning relationships with suppliers, the combination critical to the success of JIT (Just-In-Time) is communication and reliable suppliers. This approach emphasizes the need for suppliers to deliver parts and materials exactly when they are needed in the production process, thereby reducing the need for high inventory levels. With JIT, the coordination between the manufacturing plant and its suppliers is essential to ensure that parts of the highest quality are delivered on time to prevent production delays and excess inventory costs. Therefore, solid communication channels and having reliable suppliers who can deliver frequency and consistency are vital for JIT to be successful.