Life is a journey because you never quite know what is going to happen to you.
During the book, Pip experiences a variety of different life experiences once he gets his expectations that are a direct result of one two experiences—meeting Magwitch and Miss Havisham.
“Hold your noise!” cried a terrible voice, as a man started up from among the graves at the side of the church porch. “Keep still, you little devil, or I'll cut your throat!” (ch 1, p. 4)
The kindness he shows to Magwitch allows him to be able to become a gentleman and have a shot at Estella.
Miss Havisham was the second life experience that directly affected the rest of Pip’s life. He was tortured by the desire to become Estella’s equal, and by the insults she gave him.
I had never thought of being ashamed of my hands before; but I began to consider them a very indifferent pair. Her contempt for me was so strong, that it became infectious, and I caught it. (ch 8, p. 42)
Before meeting her, he never wanted anything more than the common life of a blacksmith. After his experience with Miss Havisham, Pip desires to be a gentleman so he can marry Estella, and so he will not be ashamed.
Pip’s life is even more of a journey because he has money and then loses it. When Magwitch returns, it unleashes a series of events that leads to Pip losing his fortune. But the journey so far taught him many things about life. The main thing he learned was that nothing is as important as who you are as a person.