Berlin Brandenburg Airport was originally supposed to open in 2011, but now planners expect the first passenger flights to take off in 2021 – a full decade later and billions of euros more than planned. Similarly, the Scottish Parliament building was originally projected to cost £40m when it was approved – but not only was the opening delayed, but costs spiralled to £400m – ten times the original estimate.

"39 per cent of rail projects are late and 38 per cent are over budget. Similarly, aerospace projects on average cost 61 per cent more than expected and 27 per cent are late" 

https://eandt.theiet.org/content/articles/2019/09/big-project-big-delay/

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