Which is necessary to calculate upon financial benefits or social benefits, before a personnel recruitment?

Generally, personnel recruitment targeted mostly on two reasons for a company or an organization.
One is financial benefits and other is social benefits.
Business and profit oriented company must calculate how much employee with how much salary could be provided for positive benefits.
Factory must calculate how the number of employee recruitment for more needed production.
Social and governmental organization must count the sanctioned vacant/created post to recruit for better service.
Hospitals must estimate the capabilities and number of patients to recruit doctor ,nurse and assistant.City Corporation must calculate the number areas of city to recruit the cleaner and other personnel.