When he was in art school, sculptor Auguste Rodin was tasked many times with going to the Louvre and picking an eighteenth century painting to closely observe. After leaving the Louvre, Rodin had to then draw his chosen painting from memory.
This early experience of Rodin shows that memory isn’t exclusive to genius. Memory is just like a muscle which can be exercised like Rodin did in his early years.
Musicians can especially learn from this. It’s something I know I have to work on: from engaging in more sight reading to learning parts of pieces through visualization. A musician’s memory can always get stronger.