Why is designing for sustainment a critical function for military equipment?

Designing for sustainment is critical for military equipment because it ensures that systems remain operational over their intended lifespan with minimal downtime and logistical burdens. Effective sustainment design incorporates factors like maintainability, reliability, and ease of repair, which are essential for mission readiness in dynamic environments. Additionally, it helps manage costs over time by reducing the need for frequent replacements and repairs, ultimately enhancing operational efficiency and effectiveness in military operations.