Disneyland opened at less than 80% completion, and Opening Day was a disaster. But Walt Disney saw the park as a living thing and embraced the idea that his creations would never be truly "done.".
Book: Disney's Land: Walt Disney and the Invention of the Amusement Park That Changed the World
Disneyland's opening day on July 17, 1955, was a famous disaster. Because the opening was tied to a live TV broadcast, the deadline was absolute. Disney had to open even though the park was only 80% finished.
Crews spray-painted dead grass green. Asphalt melted in 100-degree heat, trapping women's heels. The park ran out of food and water. A boat went off track, and passengers swam to shore. A gas leak shut down part of the park.
Critics called it a "nightmare," but Disney wasn't discouraged. He viewed Disneyland as a "living, breathing, constantly evolving story." Unlike a movie, which is finished once it's on film, a park could be continuously improved.
He called this process "plussing": the endless act of adding to and improving what was already there.
This aligns with the idea that Ready is not Feeling. By shipping at 80%, he allowed the park to start living and growing with its audience. The finishing movie part also reminds me of the Double meaning of Release.