Why is the overhead mirror the most dangerous piece of equipment on a school bus?

The overhead mirror on a school bus is considered one of the most dangerous pieces of equipment because it can create blind spots for the driver, making it difficult to see children who might be outside the bus or approaching from behind. If the mirror is not properly adjusted, it may not provide a clear view of critical areas, increasing the risk of accidents during loading and unloading. Additionally, reliance on the mirror alone may lead to complacency, causing drivers to overlook the need for direct visual checks around the bus.