I've never really thought about this before, but how many years should a ride at Disneyland (I'm sorry, of course I meant "attraction and / or adventure") last before it's replaced? I kind of take for granted a ride like Pirates or Mansion is pretty much going to be there for the rest of my life, but will it? I have noticed lately that Pirates is starting to look a little bit hokey. The animatronics look 1960's to me and the fire effects have never, ever been even remotely convincing. So does it really have another 30 or 40 years in it? And what about a ride like Space Mountain, that just a roller coaster in the dark? Yes, it's a lot of fun and still one of my favorites, but it has no story to it and no memorable music. So is it's shelf life longer then Pirates because it does not have animatronics and effects that can eventually look cheesey and outdated, or is it shorter because there is no story or music that park guests can get attached to? I'm going to guess longer, because Space Mountain can be redone and rethemed as much as they want. They've talked for years about upgrading DL's ride to Mission 2 from DLP. If that happened they can probably extend the shelf life by a couple of decades. Pirates gets a boost from the success of the movies, but that won't last forever. I'd love to see them close the ride down and basically rebuild the whole thing from the ground up with the most modern and advanced animtronics and sound system available, but I don't see Disney doing that anytime soon.
Obviously every ride is different. Some rides might only be around for 20 years and some might be around for over 50. But what should the expected shelf life be for an average ride at a Disney theme park? I think if I were an imagineer designing a ride, I think I'd probably think about the average lifetime of a person. For someone who grows up going to Disneyland their whole lives, how should the park look when they're 70 years old as opposed to when they were 7 years old? I would expect that more than half of the rides would have been replaced, but I would want there to be a handful of rides (and not just "kiddie rides") that they can go on when they are 70 that they remember from when they were 7. So I'm going to say that the high end of a ride's shelf life would be 70 years, and the low end would probably be 20. Any less then 20 and I think the ride would be considered a failure. So you could split the difference and say that the average should be 45 years. However, since I do think that more than half of the rides should be upgraded by the time someone is 70, I'm going to take off a few years. So I'm going to say that the average shelf life for a ride at a Disney theme park should be 40 years. Some (like Pirates and Mansion) will be longer, and some good ones will be shorter (Journey Thru Inner Space), but I think that's the number I'd probably shoot for.