That is not dead which can eternal lie, yet with stranger aeons, even Death may die.
H.P. Lovecraft
I firmly believe that this quote can be applied to horror in all its varied cloaks and disguises. True horror never really dies. It may lurk, recede from our collective consciousness from time to time, lying fallow, allowing fakes and charlatans to cloak themselves in its guise, and readying itself to come round again and blow our socks off.
It takes time for a horror author to craft a good horror story. It's not done in a day or a week or a month or even a year. True horror is a learned craft, like medicine or oil painting. It doesn't just happen and those who think they're writing "horror" all too often are writing something that touches upon horror, but is more realistically romance with trappings of things they think are horrible. Examples are Dark Shadows (the TV series, not the movies - the movie House of Dark Shadows is virtually a classic evil vampire movie full of vicious killer vampires and blood), Twilight, TruBlood, Kindred: The Embraced, and a few more. These programs and books attempt, rather openly, to disguise a classic romance soap opera by draping it with the trappings of a few hints of the horror genre. Note that all of the referenced works drape their offerings in vampirism as if vampires are the ultimate in horror.
They ain't.
In fact, Kindred: The Embraced and Twilight share so many features that I'd have a squad of lawyers chasing each other's tails if I was the designers of the original RPG or the author of the books (but we know which came first and who stole what from whom). But I digress...
Vampires are not horror anymore. They can be horrible, but the idea of vampires has so infested our cultural more's that we cannot even conceive of them as being all that horrible or "bad" anymore these days.
There are other things that affect our every day lives that are far more horrible.
The trick is to find and expand upon the genre and mythology in such a way so as to find a new way of presenting an ancient and undying idea and feeling to new readers.
We used to do it around a campfire. Then it was called a ghost story. Today we do it in books and in the theaters.
Usually badly.