It is difficult to justify with “the usual” justification for a vaccine that was authorized within a year when normally it takes a lot longer. Also it is difficult to justify an experimental mrna vaccine which had never been used before. Usually vaccines were dead virus strains introduced into the body so that the body builds immunity for it. But now with mrna we are talking of a totally changed definition of vaccine. So nothing really is usual besides a corporation’s quarterly goals of more and more profit.