From today's New Scientist homepage
Here was my comment in full:
"Have you ever known anything to cost less than originally forecast?
That would break an immutable law of grant-seeking. Estimates are always pitched low initially, so as not to frighten off the fund-givers. They are then gradually and expensively racked up to take into account a host of hitherto unrecognized factors that no one could possibly have forseen, because their eyes were deliberately focused on the far horizon, and nothing so immediate and mundane as the nitty-gritty.
The maximum final/initial ratio is reckoned to be in the region of 3:1 for seasoned pros, who know how far they can push their luck. One notable exception are the organizers of the 2012 London Olympics, who are pushing the envelope, as they say, up into new unheard-of brass neck ratios. Hidden costs, like VAT for example, which no lobbyists, least of all at ministerial level, could possibly have forseen."