Looking back at cinema history, you'll realize many great directors started out making horror films. Why?
Because you could film one cheaply, plus a horror movie is much easier to market than say, a drama. And back in the day, if you wanted to start out in Hollywood, you went to work for Roger Corman, the king of low budget B movies, making whatever was popular at the drive-ins at the time.
This is how Francis Ford Coppola, and innumerable other filmmakers first broke into the business, and Corman probably launched more great filmmakers in Hollywood than anyone.
He took on young talent knowing they'd be willing to work for practically nothing, and he'd give you your crucial first break in return. (As Beverly Gray reported in her biography of Corman, Roger would often tell filmmakers, "I get the money; you get the career.")
Coppola's next movie is Twixt, which the director describes as, "one part Gothic romance, one part personal film, and one part the kind of horror film that began my career." Again, like many directors starting out, Francis directed a scary movie early in his career, Dementia 13, which he shot in Ireland. It's a pretty good little thriller, and according to Michael Schumacher's biography of Coppola, Corman had extra scenes put into Dementia 13, by another director, Jack Hill (Coffy) because he wanted more sex in the movie.
Corman usually told his filmmakers how many exploitable elements he wanted in his films, like nudity, gore, car chases, etc., and as long as you did that, and the movie was in focus, you could make whatever you wanted. In the book Easy Riders, Raging Bulls, it was reported when Martin Scorsese made a film for Corman, Boxcar Bertha, Roger told the director there should be a nude scene every ten pages of screenplay, or every ten minutes of the film.
Although it's not a horror film per se, Coppola's 1974 classic The Conversation has one of the scariest scenes I've ever sat through in a theater. It's hard to get the full effect watching it on TV, but there's a segment where he plays with the sound mix volumes, and the soundtrack becomes so loud, oppressive, and frightening, it scared the hell out of me.
Although he'd probably be welcomed by the geek community any time because of his filmography, Coppola will be appearing at Comic Con to promote Twixt, his second visit to the event. (He first came to Comic Con for his 1992 remake of Dracula.)
H orror has been lowballed a genre long enough, and many don't understand the considerable level of skill it takes to do a horror film convincingly. It's a trip to think what Coppola could have done in the genre back when he was really on top of his game, but I'm still curious to see what he can do in a horror film today.