I read many notes, and it always mention about the steps to make the BADI works.
1) declare reference variable with reference to the BADI interface.
2) call method GET_INSTANCE of class CL_EXITHANDLER.
3) call method implemented.
I have just created an implementation using BADI LE_SHP_DELIVERY_PROC. I create default value to shipment type in the method. After activating it, it works on tcode VL02N. Why don't I need to do the above 3 steps and my implementation still works? Do I only need to do the 3 steps if I create my own BADI and implementation?