Here's why:
* Pip believes Joe is his benefactor: After Pip encounters the escaped convict, he is visited by a mysterious benefactor who pays for his education and apprenticeship. Pip assumes this benefactor is his kind and loving brother-in-law, Joe.
* Joe's selfless nature: Joe is a good-hearted and selfless man who would never take credit for something he didn't do. He genuinely believes he is the one who has made Pip's dreams come true.
* The truth is revealed later: It is later revealed that the true benefactor is Herbert Pocket, a kind and generous gentleman who is a friend of Pip's mysterious benefactor (revealed to be Miss Havisham).
* Joe's role is significant: Even though Joe is not the true benefactor, his role in Pip's life is still significant. He provides Pip with love, support, and a sense of belonging, which are essential for Pip's personal growth.
Therefore, while the credit for Pip's apprenticeship ultimately belongs to Herbert Pocket, it is Joe who initially receives the credit and who plays a crucial role in shaping Pip's character and worldview.