I'm always cautious about this question, as there are many criteria (acting, story, cinematography, breakthrough style) ... one might say George S. Scott was a great actor in Patton, perhaps even The Hustler, but few would put those on a list of overall greatest movies. Directors who almost always deliver all those criteria might include Kurosawa, Fellini, Bergman, Ozu, Renoir, John Ford, Eisenstein, Antonioni, David Lean ... those who usually deliver, say, two or so of those criteria include Martin Scorsese, John Cassavetes, Jim Jarmusch, Sidney Lumet, Francois Truffaut, Louis Malle, among others. Orson Welles delivered it all once with Citizen Kane, then moved in different directions. I haven't seen all of the works of these people yet, so I'll leave my comment at that ...