I wonder why people focus so much on IQ instead of better metrics.

In this article, "The play deficit":

http://aeon.co/magazine/being-human/children-today-are-suffe...

there are these very interesting sentences:

"Other research, by the psychologist Mark Runco and colleagues at the Torrance Creativity Center at the University of Georgia, shows that scores on the TTCT are the best childhood predictors we have of future real-world achievements. They are better predictors than IQ, high-school grades, or peer judgments of who will achieve the most."

TTCT is "Torrance Tests of Creative Thinking".

People should really be much more interested in metrics like TTCT, rather than IQ tests, SAT tests or other not very relevant metrics.