What does Pip mean when he says, "I should never like Joe's trade. I had liked it once, but once was not now."

After Pip met Estella and had become infatuated with her he becomes disgusted with his present situation as an assistant to Joe in his forge. In Ch 13 he is formally apprenticed to Joe and the chapter ends with Pip telling us that he was

"truly wretched and had a strong conviction on me that I should never like Joe's trade. I had liked it once, but once was not now."

He analyses his feelings very carefully and records them in minute detail in the next chapter:

"I had believed in the forge as the glowing road to manhood and independence. Within a single year, all this was changed. Now, it was all coarse and common, and I would not have had Miss Havisham and Estella see it on any account."

Till he was sent to Satis House where he first met and became infatuated with Estella he always looked forward to becoming an apprentice to Joe but after he met Estella he became disgusted with his profession and ashamed of his low social status and in Ch.14 he tells us what he dreaded most:

"What I dreaded was, that in some unlucky hour I being at my grimiest and commonest, should lift up my eyes and see Estella looking in at one of the wooden windows of the forge."