I see countless Matrix and ATAR Notes articles/forums which illustrate the importance of practicing a subject like maths. I would consider that, by doing HSC questions alongside my textbook questions, I am 'practicing.' However, what actually happens in our brains as we do more and more maths? If one might have an extensive understanding of a certain topic, how does doing countless questions improve their ability? For example, I have come across difficult questions in the past on worksheets. I don't actively remember how I did them or what they are, but somehow, it has prepared me to answer questions with a little more difficulty each time without me actively realising it. How does this work and why does this happen?