Purpose of the contract manager role at a Resource Organization

Summary: At Tools > Resource Directory, there is a contract manager role associated with each Resource Organization. What is the purpose of this contract manager role?

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We have one employee in the contract manager role of a Resource organization and a few hundreds employees in the contract admin role of the same Resource organization. Then we are able to pull any of the employees above at a contract UI and assign as a contract party contact. The one employee in the contract manager role is now retiring. What is the impact to the resource organization if we don't assign a new employee in advance? What is the purpose of this contract manager role?