The WaitHint property specifies the estimated time required (in milliseconds) for a pending start, stop, pause, or continue ...

The WaitHint property specifies the estimated time required (in milliseconds) for a pending start, stop, pause, or continue operation. After the specified amount of time has elapsed, the service makes its next call to the SetServiceStatus function with either an incremented CheckPoint value or a change in Current State. If the amount of time specified by WaitHint passes, and CheckPoint has not been incremented, or the Current State has not changed, the service control manager or service control program assumes that an error has occurred.