Airports and infrastructure mistakes

[colmoc]

So why is it that we cant complete major engineering projects on time and within budget on a regular basis.
Thomas the airport your thinking of is in Hong Kong (largest man made island) and the bridge is the milau viaduct between spain and france visited both recently and trust me it puts anything in Ireland to serious shame.
Supposedly (i.e. correct me if I am wrong) the french government have a department of engineering which manages all structural projects that go over a certain cost. This dept has built up years of experience and knowledge of how to manage and bring a project in on time.
Ireland on the other hand gets a different team of engineers/project managers/financial controllers for each project and thus spreads any knowledge and experience gained from a project to the four corners of the world after it finishes. In that sense there is no real learning from past experience