You should develop a Pause or Proceed Plan to decide whether the current ideas can deliver the strategic objective. Changes in the external environment or development of the idea may mean that the strategic objectives no longer holds true or are viable. It is important to have planned a graceful Pause or Proceed Plan at the beginning to avoid straining relationships if the idea has to come to a stop or a pause.  Asking these questions at the outset should drive teams to define and deliver better projects and help to manage the scope.