why we provide alias names after 'DELETE' in multiple delete

This might be a very stupid questions, but I am keen to know if anyone has any suggestions:

Single Table Delete Correct Query : delete from vehicle_owner where id=3;

Single Table Delete InCorrect Query : delete from vehicle_owner v where v.id=3

Mulitple Table Delete : delete v,s from vehicle v , category s where v.id=3 and v.id=s.id;

Qs 1: I was wondering that why 1st is right and why 2nd is incorrect. Basically I am looking for logical answers which explains why providing an alias in delete query is incorrect.

Qs 2: why we keep two alias names after 'DELETE' keyword for multiple delete. Anyways we are providing complete details in join condition. So why it is designed in such a way.