Alfred Hitchcock never won an Oscar which shows how meaningless the Oscars are.
Hitchcock wasn't really appreciated until his declining years, and no one was going to give him an Oscar for Torn Curtain or Family Plot.
The 5 times that Hitchcock was nominated, the winners were no slouches: John Ford, Leo McCarey, Billy Wilder (twice), and Elia Kazan.
It is amazing that Hitchcock did not win best director for Vertigo, North by Northwest, Rebecca or Psycho. These are literally some of the best movies ever made or directed. They are by far some of the most memorable.
It is understandable when two or three incredibly great movies come out in one year and you lose to The Godfather or The Deer Hunter. Some years there just are not many good movies. Other years movies like Shakespeare in Love beat Saving Private Ryan and you just know that the fix was in.