Statistical offices do not run one survey. They run a standing portfolio, repeatedly, for decades, at very large scale. Individual offices in large countries run well over a hundred distinct surveys a year.
These instruments interlock. Expenditure surveys supply the weights for the consumer price index. The census supplies the sampling frame for nearly everything else. Labour force data feeds the national accounts. An undetected error in one instrument propagates into several published statistics.
And every completed round already sits in the archive — decades of microdata whose quality has never been independently re-examined.