Although I could have included more directors, I tried to limit it to 12, and those generally considered to be the most significant.

I love Godard's 60s films, but not really those that he did later. Chabrol's films are some of my favorites (Les bonnes femmes, Le boucher, La rupture, La ceremonie), but when he periodically moved away from his Hitchcock thriller influence to mainstream films and period pieces, I become quite mystified... Rivette's Celine and Julie Go Boating is one of my all-time favorite films, and I quite like his much later Va savoir as well, but I haven't been able to see most of his other films... Truffaut was either really great (400 Blows, Shoot the Pianist, Jules and Jim, Stolen Kisses, Day for Night), or really awful (see The Green Room)... Varda made some great early films, as did Demy and Resnais...

The one who consistently put out films I love from the beginning of his career to the end is Eric Rohmer. (It helps that it was always easy to find Rohmer's movies in video stores in the US, whereas most of Rivette's work was quite hard to find.) Guess I have to vote for Rohmer... (Torn between him and Chabrol.)