At what point did you realize you were actually learning ML, not just using libraries?
I've been learning machine learning and I keep wondering where the line is between actaully understanding ML and just knowing how to use libraries.
For example, you can train a model, tune some parameteres, look at the accuracy, and get a good result without fully understanding what is happening underneath.
So for people who have been doing ML for a while:
What concepts make you feel like you finally understood machine learning?
What is the math behind gradient descent, understanding loss functions, overfitting, reading research papers, implementing algorithms from scratch, or something else?
And what do you think beginners spend too much time learning that isn't actually that important?