There is also an issue of getting what you measure for since humans game systems to their benefit. Look at standardized tests - they guided education from an early age as opposed to actual educational outcomes. I remember vividly being in elementary school and they multiple workbooks with pages of analogies with occasional ambiguous answers. There wasn't any real learning just a bunch of drilling that depended on existing knowledge. Then the SAT dropped it for a writing section and analogies practically disappeared off the face of the earth. They showed up four times a year at most - literally. Usually because the quarterly state tests had one question with them.