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.
Frederick Gye
The opera during the seasons of 1856 and 1857, commencing 15 April 1856, was held in the Lyceum Theatre, where in the first season forty operas were given, and advertised as being under Gye's direction. The renters and proprietors of Covent Garden finding themselves unable to collect the money to rebuild that theatre, Gye with great energy raised or became accountable for £120,000, the sum which the new structure cost. The opera house, from the designs of Edward Middleton Barry, R.A., was commenced and completed in the short period of six months.