Car buyers shun celebrity endorsements when making their buying decisions, according to whatcar.com users.
In one of our most one-sided whatcar.com polls ever, just 11 people - 1% of the total votes cast - said a celebrity's endorsement of a car would encourage them to buy it. An overwhelming 87% said it would not encourage them to do so. Over 1000 people took part in the poll.
So why do car makers do it?
On the eve of the Geneva motor show earlier this year, Justin Timberlake was asked why did he become an ambassador for Audi. His refreshingly honest reply was: 'Because they paid me a lot of money.'
Getting an international popstar such as Timberlake to become a 'brand ambassador', or getting Uma Thurman to appear in Alfa Romeo commercials, for example, doesn't come cheap.
Even giving someone a little further down the A-list a 'loan' of one of your cars can be costly, so what do car makers actually get from celebrity endorsements? One source, from a car maker that didn't want to be named, told us:
'The impact of a celebrity being seen in a certain manufacturer's car will vary, depending on the profile and attributes of that brand. Would it make a customer rush out and buy a Porsche or Ferrari just because a celeb is spotted driving one - absolutely not.
'However, if a brand is trying to change its public perception or develop its profile, as part of a broader brand evolution campaign, having well-thought-through high-profile people behind the wheel is proven to help.
'The individual has to match the brand's values as closely as possible or the placement won't look credible, but a few, well-selected, well-respected and clean-living individuals driving a company's cars has been shown to have demonstratable results in terms of changing consumer perceptions.'
So who does what?
Uma Thurman is probably the highest-profile star to be in car ads in the UK, but celebrity voiceovers are much more common in car ads in the US, where Patrick Stewart (BMW), Tim Allen (Chevrolet), Jeff Bridges (Hyundai) and Robert Downey Jnr (Nissan) all have well-paid gigs with car makers.
Over here, sports stars do pretty well out of car makers. Jaguar sponsors the England cricket team, while Audi has a relationship with Manchester United that entailed a motorcade of Audi R8s leading the team bus to Old Trafford last season for a match against Chelsea.
Everest-conquering climber Bonita Norris is the face of the Nissan Juke, while sailor Ellen McArthur has a partnership with Renault.
• Whatcar.com poll asked: Would a celebrity's endorsement of a car encourage you to buy it?
Depends on the celebrity 5%
Depends on the car 7%
Poll of 1014 respondents.