"Understanding of the underlying causes of the experience curve is still imperfect. The effect itself is beyond question. It is so universal that its absense is almost a warning of mismanagement or misunderstanding. Yet the basic mechanism that produces the experience curve effect is still to be adequately explained. (The same thing is true of gravitation.)"
Boston Consulting Group - 1973
"...the actual costs of 75 of the existing nuclear power plants in the U.S. exceeded the initially estimated costs of these units by over 200 percent."
Nuclear Power Plant Construction Costs - July 2008