But Disney isn't perfect, many of the common complaints you hear about Disneyland are "No new E-Tickets since Indy", DCA "Had to spend Billions to fix 1/2 a park", WDW "Magic Bands, no new rides", etc.
Disney has figured out how to expand attendance or at the very least keep it's level of attendance without having to add something new every year. This has a lot to do with the Disney "brand". For us theme park nerds, this sometimes causes us to bash Disney, especially when we see other park chains expanding every year and in some cases at a lightning speed rate.
Disney's fan base is so large, has so much disposable income and is more loyal than any other theme park fan base ... and Disney knows this. Year after year people drop thousands on Annual Passes, DVC, RunDisney races, merchandise and movies that simply adding something "large" to each property about once a decade seems to be enough to keep people coming through the turnstiles.
Disney knows how to crank up the nostalgia like nobody else. Where anniversary's for theme parks become huge events in and of themselves. No need to spend $100-$200 million on a new E-Ticket when spending 1/4 of that on a year-long Anniversary celebration will bring in the same amount of people.
No need to build a new dark ride when adding new elements to existing rides (Hatbox Ghost, New effects to existing rides) increase ridership and keep people coming in.
That's not to say these things aren't great, because they are, but obviously Disney knows what they are doing (duh).