Hi Jharna,
As Prem said in the 3rd point - what could the management have done to retain you? And in the last paragraph, if he/she is worth it, the management can retain him/her. The main purpose of an exit interview is to have a healthy discussion with the employee who is leaving and to assess the reason behind it.
If the person is leaving because they are not receiving enough money here and the management, after conducting the exit interview, finds that the person is worth a raise, they can ask - "If we raise your salary, do you think you will reconsider your decision?"
The exit interview process varies from company to company. In some companies, there is a pre-exit session, which is essentially a counseling session, held just after the employee has submitted their resignation. Asking such questions can assist the management in identifying problems and potentially help the company retain the particular employee.
Regards,
Anuradha