I'll second what
@horsesboy said. I think a lot of people (including me) don't actually find haunted houses "scary" in a literal sense. You always know in the back of your mind that it's a safe, controlled environment. "Startles" is probably better word than "scares" for me, because there are still jump-scares that get me, and that's the fun of it. But jump-scares alone get old quickly. I think the magic of haunted houses is that they're a combination of immersive themed environments and what's essentially interactive theater - with an added layer of thrill coming from the suspense of a jump-scare that could happen at any moment.
In an ideal haunted house, all three of those elements are present: immersive environments, storytelling, and suspense. And they play off each other. A spooky environment that makes you feel like you're somewhere other than a theme park, a well-conveyed story that helps you suspend disbelief and pretend you're really in that environment, and the looming threat of a jump-scare to give everything a bit of stakes... that's the secret sauce. The spookier the environment, the more the storytelling and effects can play on your senses, the more your primal instincts get the better of you when a monster jumps out at you unexpectedly, the more fun the experience.
It really is all generally for fun, IMO. The main reaction of me in a haunted house is laughter, along with maybe the occasional "Oh shit!" blurted out if someone gets me good. I think it's a totally different goal than a horror movie, for example, where the realism and phycological tricks (and all the other characteristics of film as a medium) can create something that's genuinely, deeply disturbing and not just comically gory or scary for laughs like a haunted house. (I say this because I'm a total weenie when it comes to horror movies and want to make clear that my finding haunted houses funny isn't just a pathetic attempt to appear stoic.)
To that end, I think it's possible to judge haunted houses somewhat critically and objectively without being jaded by how well you handle scares. They can be judged much like any other theme park attraction or show. If BGW sticks a bunch of scare actors into a sparsely decorated black-painted plywood hallway, that's not a good haunted house, even if every scare actor is on their A-game and gives you a jump scare at every turn. Likewise, a beautifully built haunted house can only be so effective if either the actors aren't trained to convey the story (or scare well) or the house is poorly staffed; this seems to be a perennial problem for KD's Trick or Treat, for example. (I think the latter problem is less important because walking through a well-built environment is still somewhat enjoyable, and training/staffing is a problem that can be more easily solved than getting the basics of house design right).
All this to say... I've never really stopped to think about what makes haunted houses such a uniquely fun medium before. They're pretty cool. I love this time of year.
