What is the hazard of "Under excited"?

The hazards of under excitation:
Voltage drop: It causes the system voltage to decrease, affects the power supply quality, and may cause electrical equipment to fail to work properly. For instance, some motors may have a reduced rotational speed or stop operating due to insufficient voltage.
Insufficient reactive power: It fails to meet the system's demand for reactive power, affecting the efficiency and stability of power transmission.
Increased line current: Due to the voltage drop, in order to maintain power transmission, the line current will increase, thereby increasing line losses and heat generation, which may trigger line faults.