From the new afterword to David Epstein’s book, Range:
One of the earliest recorded uses of the phrase “Jack of all trades” as an insult dates to 1592. In the New Latin form “Johannes factotum,” it was contained in a pamphlet by a playwright criticizing his own industry. The jab refers to a poet with no university education who was apparently involved in various other roles, like copying scripts and bit-part acting, even trying to write plays. The poet on the receiving end of the insult: a young William Shakespeare. The phrase evolved over time, and today it’s usually “Jack of all trades, master of none.” I think it is culturally telling that we habitually hack off the end of the long version: “A Jack of all trades is a master of none, but oftentimes better than a master of one.”