What is the meaning of the sleep detection exception that involves a callback being made on a delegate that has been garbage collected?

edit

This exception typically occurs when a program attempts to access an object that has already been garbage collected. Specifically, it occurs when an application uses a delegate to reference a method for sleep detection, but the delegate has already been garbage collected by the time the sleep detection method is called. Consequently, the program cannot execute the sleep detection method, resulting in the exception being thrown.