The real question is how do we define "success"? Is success making a lot of money? How much is enough to qualify as "successful"?
We tend to narrowly define success based solely on extrinsic values like money and status, rather than intrinsic values like mastery, purpose, and happiness.
I think the author is saying that focusing on mastery is more likely to lead to "success" in the form of happiness and a greater sense of purpose, regardless of whether or not it also leads to material wealth. Personally, I agree with this more holistic view of success.
Each individual has define success and wealth for themselves. Money is a default because it is easy to measure, this does not mean it is the right metric to use.
We tend to narrowly define success based solely on extrinsic values like money and status, rather than intrinsic values like mastery, purpose, and happiness.
I think the author is saying that focusing on mastery is more likely to lead to "success" in the form of happiness and a greater sense of purpose, regardless of whether or not it also leads to material wealth. Personally, I agree with this more holistic view of success.