What motivated the author's brother to seek a deeper understanding of Stein's work?

The author's brother was motivated to seek a deeper understanding of Stein's work due to his dissatisfaction with initial explanations. This suggests that the brother found the initial interpretations or discussions inadequate or lacking in clarity, prompting him to dive deeper into the text. By feeling that these early explanations did not sufficiently illuminate Stein's writing, he was inspired to explore the work more thoroughly, seeking to grasp the nuances and complexities on his own terms. This motivation highlights an intellectual curiosity and a desire for a more comprehensive comprehension of the material, ultimately indicating that a meaningful understanding of literature can require more profound engagement than superficial explanations offer.