The statistics are wrong, but always wrong in the same way; the conceptions are fanciful, but it is always the same fantasy.

From The Anti-Politics Machine by James Ferguson.  Page 55.

The peculiar representation of Lesotho which emerges from the World Bank report must not be understood as simply the product of mistakes or errors. There are, indeed mistakes and errors in the Report just reviewed, and there are nearly as many in most other such reports. But these mistakes and errors are always of a particular kind, and they almost invariably tend in predictable directions. The statistics are wrong, but always wrong in the same way; the conceptions are fanciful, but it is always the same fantasy.

 

Lightly related to the adage from statistician George Box.

All models are wrong, but some are useful.