The full saying is "No one ever went broke underestimating the intelligence of the American people/public," or some variation thereof, meaning that people being swindled won't realize or question it, which makes them a prime source of income for others. It is typically attributed to writer H.L. Mencken. A: "We can't sell this shoddy product to people!" B: "Oh please, no one ever went broke underestimating the intelligence of the American people."

The full saying is "No one ever went broke underestimating the taste of the American public," or some variation thereof, meaning that people will gladly accept something lowbrow or inferior, which makes them a prime source of income for others. It is typically attributed to writer H.L. Mencken. A: "We can't pitch this script to the studio—it's truly awful!" B: "Oh please, no one ever went broke underestimating the taste of the American public!"