When a measure becomes a target then it ceases to be a measure.
From BBC News, 25 September 2015:
According to the Environmental Protection Agency (EPA), some cars being sold in America had devices in diesel engines that could detect when they were being tested, changing the performance accordingly to improve results.
“We’ve totally screwed up,” said VW America boss Michael Horn, while group chief executive Martin Winterkorn said his company had “broken the trust of our customers and the public”.
— John F. Allen (@ProfJohnAllen) October 1, 2015
From this blog, on Research Assessment and REF:
And where changes in rank order are discernible, the question will remain: has anything actually changed? Or do the results reflect differing tactics, and choice of measures as targets?