How to delete Shift Setup?

A shift is a period of time that an employee or group of employees works. Shift setup is the location that shows all the shifts under one page for the respective company where the settings can change as well as "add new shifts"

Shift can only be deleted if that shift is not used ( employees are not assigned under that shift) but if that shift is used ( If an employee is assigned even once) it can never be deleted. The following error message will pop up when the user tries to delete the shift to avoid the deletion.

note: kindly consider this is not a system error and this is a user message while deleting a used shift.