After a case has been granted certiorari which is when four Justices agree to review a case it is then the justices may decide against further review of the case. They can review a case an decide to dismiss it if Court may feel the case presented during oral arguments did not present the constitutional issues in a clear-cut way. In this event the writ of certiorari is "dismissed as improvidently granted" (DIG)—saying, in effect that the Court should not have accepted the case. Harsh right XD
The Supreme Court accepts 100-150 of the more than 7,000 cases that it is asked to review each year. - Us courts website claims this number
