I've not went and read any of the actual studies, only the article, but it seems that they start measuring kids around the age of 10 onwards, is this not too la

I've not went and read any of the actual studies, only the article, but it seems that they start measuring kids around the age of 10 onwards, is this not too late? One of the themes seems to be that certain measurements of ability at this age were accurate indicators of future success if the kids were not discouraged (ie allowed to push themselves and learn more advanced stuff). But by age 10 surely most kids have already been discouraged? I was reading another article earlier today that I can't find talking about pre-school being more important for life chances than high school. Could it be far more kids than we think are capable of being 'geniuses' and that the majority are discouraged at an early age? I'm not read up on this so if anyone is please share!