Planning fallacy
The Sydney Opera House was expected to be completed in 1963. A scaled-down version opened in 1973, a decade later. The original cost was estimated at $7 million, but its delayed completion led to a cost of $102 million.
Opera House, Royal Tunbridge Wells
Construction was completed in 1902 to designs by architect John Briggs. When it was opened, it had a capacity of 1,100. In 1913, the Opera House hosted a series of charity fundraising concerts gather funds to rebuild the Nevill Ground's cricket pavilion after the original pavilion was destroyed in a suffragette arson attack. The Opera House was purchased by Union Cinemas in 1931 and turned into a cinema.