Why did people become pirates?

Many people who became pirates did so to escape their menial jobs in London, the Royal Navies, or the Caribbean colonies; some were criminals already and decided it was all or nothing; and of course, some were escaping persecution. It appears some were also doing it for revenge. According to this (which admittedly could be a bit suss), significant numbers of pirates were Jews seeking to wreak vengeance on the Spanish Crown for its support of the Inquisition. Some were pretty good at it too apparently.