The lesson focuses on enhancing the functionality of a Go program that counts lines, words, and bytes in a text file, similar to the Unix `wc` command. By modifying the `count_words_in_file` function to return multiple attributes, the approach emphasizes creating a more readable code structure using named return parameters. However, challenges arise, such as the potential for confusion regarding return values and the risks associated with "naked returns." To address these issues while maintaining clarity, the concept of encapsulating return values within a struct is introduced, allowing for improved organization of data without sacrificing clarity. The lesson also hints at a bug related to the order of function calls that will be resolved in future discussions, illustrating the importance of thorough testing and debugging in code development.