There have been a lot of good horror movies, there have been a lot of bad horror movies made as well. Sometimes a horror movie becomes a classic, but is dated. The references are lost on the youth of today. Sometimes a director will see an old low budget horror movie and think he can do better simply because his budget will be bigger.
Bottom Line: Horror movies get remade a lot. A LOT!!!
Are any of those remakes worth it? Think about it. Can you name one single horror remake/reboot that is worth the price of admission? The two that immediately come to mind for me are The Texas Chainsaw Massacre (2003) starring Jessica Biel. That movie was solid, and scary. Nothing compared to the original, but a worthwhile entry. Secondly, Rob Zombie's Halloween (2007). Zombie gave Michael Myers a back story which was met with a lot of criticism. I liked it. Not everyone did. The movie is no doubt flawed, but I'll allow it.
CLICK HERE to revisit horror movie remakes of the 2000s and the most worthwhile entries.