For employees who wish to leave, HR needs to ensure that their Exit interviews are done and feedback is recorded. HR also needs to ensure that Notice Period and other relevant information is determined.
A few days before the employee's exit, HR needs to ensure that all the departments in the company have done a handover from the employees so that the employee can be relieved. HR needs to co-ordinate the process of issuing a No Due certificate to the employee so that the Final Settlement can be processed.
All relevant information should then be considered in Payroll. HR needs to provide a feedback to Management on why employees are leaving, the attrition rates, etc.