What do notification messages provide to the operator?

Notification messages serve a critical role in providing the operator with essential information regarding the robot's performance and operation. The correct answer emphasizes that these messages are designed to inform the operator about how to effectively control the robot, ensuring that the operator has the necessary insights to manage the robot's actions and responses accurately. This capability enhances both operational efficiency and safety, allowing the operator to make informed decisions while working with or alongside the robotic system.

In contrast, confirmation of errors, instructions for safe operation, and the current state of the robot are important aspects of robot management but don't encapsulate the broader and more functional purpose of notification messages in the context of robot control. While those elements may be part of a notification system, they do not specifically focus on providing the comprehensive information needed for effective robot control as highlighted in the correct answer.