Dear Mr. Krupakar Reddy,
It depends on the policy of organization & this is not necessary,
If there is requirement then you have to fulfill the vacancy for smooth operation in your organization & Second things is manpower requisition manpower requisition form will help you define the roles and responsibility of that Individuals in your organization, this will help you to prepare organization chart and show his status (i.e. to whom he has to report ), help you to prepare annually budget. because manpower requisition forms contains all relevant data about that and requisitioner will fill all the data like what should be the qualification, total years of exp. what works generally he will complete and what salary will be.
So manpower requisition will help you to define all the matters.
With Regards