Would having prominent "cancel order" and/or "edit order" buttons and delayed payment processing have sufficiently reduced the support costs for such cases? (I

Would having prominent "cancel order" and/or "edit order" buttons and delayed payment processing have sufficiently reduced the support costs for such cases? (I am guessing not since such is an obvious method of providing a fast/easy default with a somewhat easy undo, but sometimes the obvious is missed or turns out to add problems -- like people seeing a prominent "edit/cancel order" and assuming it meant 'confirm/place order' as used by every other site.)