Final answer:
A stable, level, mixed product model production schedule is indeed advantageous for JIT/lean systems because it promotes efficiency and aligns with the goals of reducing waste and meeting customer demand. The statement is false.
Step-by-step explanation:
The question whether a stable, level, mixed product model production schedule is not advantageous or necessary for JIT/lean systems is false. Just-In-Time (JIT) and lean systems emphasize the need to avoid waste and enhance efficiency by producing only what is needed, when it's needed, and in the amount needed. Having a stable, level production schedule aligns with the goals of JIT and lean systems by enabling continuous flow and reducing the potential for overproduction and excess inventory. In a mixed model production, products with varying demands are produced in a way that levels the total production volume to create stability in processes and workflows. Thus, a stable production schedule is advantageous for JIT/lean systems as it promotes efficiency and responds effectively to customer demands.