Here's why:
* Brock's Journey: Brock is trying to prove himself as a trainer and wants to test his skills against strong opponents. However, his father believes that he's not ready for the challenges that lie ahead, especially against a young and ambitious trainer like yourself.
* Protecting His Son: He's concerned about Brock's safety and wants to shield him from potential injuries or setbacks. His love for his son motivates him to act as a barrier.
* The Value of Experience: The old man understands that experience is crucial for growth. He believes that Brock needs to hone his skills further before facing a trainer like you.
* Character Development: The old man's actions also add a layer of depth to Brock's character. His father's concern highlights Brock's desire to prove himself and his determination to become a strong trainer, despite the limitations placed upon him.
You can't defeat the old man, as he's more of a symbolic obstacle representing Brock's father's concern. To get past him and into the gym, you'll need to convince Brock to battle you.