about the Work Performance Infromation

The Work Performance Infromation is the key output of the Direct and Manage Project Execution Process... and will be the input of
1. ALL the Monitoring & Controlling Process Groups (deside Schedule Control Process)
2. Close Project Process. ( for final closure report)
and
3. Perform Quality Assurance Porcess. ( for the activities to improve process quality)

My question is ......


Why isn't the Work Performance Infromation also the input of Schedule Control Process?
Needn't we use Work Performance Infromation to Control our shedule ?
Shouldn't we compare the data from Work Performance Infromation with shedule baseline?


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