Just days before its highly-anticipated initial public offering, social networking giant Facebook has received a very public slap in the face from car giant General Motors: it has told Facebook that it will no longer advertise with it because the ads just don't work.
The loss of $10m in ad revenue is not likely to dent Facebook's market value, which is on course to sale past the $100bn mark when it floats. Last year Facebook made $3.7bn in revenue.
But the public rebuke over the effectiveness of advertising on the social network will undoubtedly sting.
According to the Wall Street Journal, which first reported GM's shift in advertising strategy, the car giant spends around $40m each year on Facebook – three-quarters going on social content and $10m on advertising.
The implication is clear: Facebook's a great avenue for businesses to connect with their customers, but spending money on adverts is simply over-egging it.
And GM is not alone in questioning the value of Facebook advertising.
According to research by online ad analysts WordStream, Facebook ads generate far fewer click-throughs than those placed with arch-rival Google. WordStream claimed the average click-through rate on Google display ads is 0.4 per cent; with Facebook it's just 0.05 per cent.
Such measures matter little when Facebook can generate rampant demand for its stock ahead of its IPO. But as a public company, it will be beholden to shareholders that demand revenues grow – so expect to see Facebook double down on its ad offerings in the very near future.
Cotton seedling freezes to death as Chang'e-4 shuts down for the Moon's 14-day lunar night
Fortnite easily out-earns PUBG, Assassin's Creed Odyssey and Red Dead Redemption 2 in 2018
Meteor showers as a service will be visible for about 100 kilometres in all directions
Saturn's rings only formed in the past 100 million years, suggests analysis of Cassini space probe data
New findings contradict conventional belief that Saturn's rings were formed along with the planet about 4.5 billion years ago