Moby Dick sold fewer than 3800 copies when it was first published, and ruined Melville's career.
Adam Rifkin stashed this in Factoids
Stashed in: Books!
Source is this Mental Floss article:
Reviews were merciless. The London Athenaeum called Moby-Dick “trash belonging to the worst school of Bedlam literature.” The London Literary Gazette said the story made readers “wish both [Melville] and his whales at the bottom of an unfathomable sea.” The New York United States Magazine and Democratic Review charged Melville with crimes against the English language.
The poor reception wasn’t entirely Melville’s fault. The British first edition accidentally omitted the epilogue. The publisher also deleted 35 crucial passages to “avoid offending delicate political and moral sensibilities.” But those excuses linger only as a footnote. Critics and fans alike had expected a wild ocean adventure. Instead, Melville gave them a 635-page philosophical brick.
Just 3715 copies of Moby-Dick were sold in Melville’s lifetime. The book earned him a measly $556.37 in the United States. His popularity plummeted—and so did his bank account. “Dollars damn me,” he griped earlier to Hawthorne. “What I feel most moved to write, that is banned—it will not pay. Yet, altogether, write the other way I cannot.” Within a year, Hawthorne stopped writing back. Their friendship dissolved.
In 1863, Melville returned to New York City and became a customs inspector. He held the job for the rest of his life, quietly writing poetry in his spare time. In 1867, Melville’s oldest son killed himself, sending the already alcoholic author spiraling into depression. The day after Melville died, his obituary appeared in just one newspaper. It was a paltry six lines long. Melville would have to spend three decades rotting in a pine box before critics realized there was more to his story.
Had he been successful with Moby Dick, he would have written more.
How Moby Dick itself got resurrected is a good story, available at the Mental Floss link.