You miss my point. That type of attraction (Earthquake/Disaster), like the physical elements in DHS's former Backlot Tour sections & effects, have a tendency to degrade quicker than a typical theme park attraction. Twister was in the same boat with special physical effects that degrade over time due to the unusual stresses put on them . The two shows on Backlot Tour weren't too pretty at the end either. Thus the shorter shelf life for attractions of that nature. Whereas many of Disney's theme park attractions have been around for a long time, even their newer attractions are the same age as Disaster was.