Pigeonholed Director

I am a typed director. If I made Cinderella, the audience would immediately be looking for a body in the coach.

—Alfred Hitchcock

Essentially the director's equivalent of Typecasting, where certain directors are linked to a certain genre they work in, or are best remembered for one or more certain films.

Examples of Pigeonholed Director include:

All but two of James Cameron's films are science fiction.
David Fincher: Expect it to be gritty, stylish, morally murky, and concerning criminal goings-on (The Curious Case of Benjamin Button is the only outright exception so far, The Social Network fits the bill aside from the grittiness)
Steven Spielberg is remembered for tales of childlike innocents or intrepid adventurers (or both) triumphing against an unforgiving world, usually in a sci-fi setting.
Stanley Kubrick outsmarted genre pidgeonholing by making a classic in every genre, sometimes more. All the same, he's best known for filming with a cold, controlled eye and slow, steady pacing.
David Cronenberg, despite Playing Against Type in recent years, will always be a pioneer of Body Horror.
How many non-Thriller films has Alfred Hitchcock done again?
- Mr. and Mrs. Smith—A Screwball Comedy. (Not that one.)
Quentin Tarantino doesn't have a genre sterotype, unless "throwback" is a genre. Also, expect characters in his movies to discuss other movies, also for the plot to occasionally stop for a while so people can trade witty banter.
David Lynch: Mind Screw. Lots and lots of Mind Screw. (The Straight Story excepted)
Martin Scorsese has become synonymous with (organized) crime dramas, even though he's tried just about every genre you can imagine: musical, romantic comedy, documentary, Biblical epic, costume drama, even a biopic about the Dalai Lama.
Akira Kurosawa is mostly known for his samurai films in America but also made a number of films about contemporary post-war Japan.
Michael Bay: Big, dumb, loud, action-heavy, vaguely misogynistic, even more vaguely racist, with thin characters, shakey plots and terrible dialogue, and things go BOOM a lot.
The Wachowskis: Cyberpunk (or at least dystopia), in a flashy and stylized manner, with a strong anti-authoritarian streak, and a lot of philosophizing. When they tried to do something Lighter and Softer with Speed Racer, audience and critical reception was ugly.
Terrence Malick: Slooooooow and pretty and introspective.
Christopher Nolan: Neo-noir, non-linear, psychological thrillers with obsessed protagonists.