One of the unintended casualties of traditional test-taking is the important attribute of tenacity.  Imagine you are a student who does badly on tests in, say, algebra.  When you get a test back, there may be a review of the correct answers, you put the test away and move on to the next unit with the rest of the class.  Because there is no mechanism for learning from your mistakes, you are prevented from responding to the problem, whatever its cause.  You are, in effect, being trained to acquiesce in the face of failure.

This experience is, of course, demoralizing and even humiliating, especially if it happens over and over.  Equally bad, an opportunity to learn to have grit in the face of adversity is being squandered;  students are trained not to have tenacity, to stand back up and figure out how to recover.  Multiply this experience by millions every day in schools everywhere, and you can see how this one structural problem can have widespread social consequences.  

The ability to see mistakes and failure as feedback is an essential attribute of an effective learner.  So is having grit in the face of negative feedback.  

Grit is an essential attribute of self-directed learners.  Without it, the motivation to persevere when the going gets tough dwindles, and the learning process is stymied.  Test remediation techniques can directly train students to have tenacity in the face of failure.  Students can learn to push through self-imposed ceilings on the their academic success.  And in so doing, they also practice a life skill that is important in every future endeavor.