What is the consequence of operating the engine below the MOR limitations?

Operating the engine below the Minimum Operating Requirements (MOR) limitations can lead to potential engine damage. MORs are designed to ensure that the engine operates within specific parameters that guarantee both performance and safety. If the engine operates below these limits, it may not perform as intended, which can lead to overheating, excessive wear, or even catastrophic failure over time. This principle relies on the fact that engines are built to withstand certain thresholds, and operating them outside of these ranges compromises their integrity and functionality.

In contrast, the other options do not accurately reflect the implications of operating below MOR. Decreased fuel efficiency and increased thrust output would not necessarily be intertwined with operating below these limitations, and improved performance safety is also negated when an engine is not functioning within its required operational parameters. Hence, recognizing the risk of engine damage is crucial for maintaining operational safety and integrity.