You can easily “win” an IQ test: just memorize the answers (ignoring the fact that not everyone, in fact, can easily memorize a lot of random stuff like that).

You can easily “win” an IQ test: just memorize the answers (ignoring the fact that not everyone, in fact, can easily memorize a lot of random stuff like that). Of course, no reasonable person would say that a person who memorized all answers in IQ test to get a score of 150 has really improved her mental ability. The situation is somewhat the same with SAT, but it’s not so bad in actual reality: there is no single SAT test, there are multiple instantiatons, and you can’t just memorize all answers for all SAT tests. At the same time, the actual problems on the test come from a rather limited pool of patterns, and if one learns to tackle each pattern, one can really improve their SAT score. This is, in fact, perfectly commonplace: everyone significantly improves their SAT score between grades 8 and 12 (at least among people who do take SAT at both ages). Does it make SAT useless, as everyone learn all the patterns and gets perfect score? Empirically, no: there is large variation in actual obtained scores, and the results are mostly in expected directions: “better”, “smarter” students get better scores and vice versa. Why doesn’t everyone get perfect score? Quite simply, because variation in mental ability also makes it so that learning the pattern is easier to some people than it is to others. This is by far the source of most of the variation: there is some residual component of conscientiousness, but it’s much less important: spending more time cramming has lower returns the less able you are, and for everyone, there are significant diminishing returns to extra hour of cramming, and ultimately high scorers don’t differ that much in terms of how much time they spend prepping to SAT compared to mid-scorers.