This weekend, for the 14th time on the trot, Audi will line up to take the start at Le Mans. And with four cars entered and the only other cars with the raw pace even to hope to challenge its dominance being a brace of hitherto unraced Toyotas, I suspect the outcome of the race has never been more easily predicted.

The question is why does Audi come back year after year? I have long inclined to the view that if the only news worth reporting is when you don’t win, it’s time to do something else. Audi begs to differ. It will tell you that even at the top level, winning in sports cars requires a tiny fraction of the budget you’d need to be an also ran in F1. It will also point to its brand, which has never been more successful or more globally highly regarded than it is right now. And it will insist that the lessons it learns chuntering around western France for a day and night will in time benefit the people who drive their road cars.

But does racing really improve the breed, or is that a convenient excuse, a way for car manufacturers to claim solid consumer benefit for what is actually a mere marketing exercise?

There is no doubt that technologies perfected on the track have found their way onto road cars. Would a McLaren F1 have had a carbon fibre monocoque had the MP4 not have one 14 years earlier? And would today’s most expensive and sporting road cars still have carbon ceramic brakes had the technology not first been proven in the white heat of racing? I very much doubt it.

But there are two points to make here: so far these innovations and others such as downforce generating bodywork, underfloor aerodynamics and road-legal tyres that provide almost as much grip as pure racing rubber, have benefitted a number of cars that, seem on a global scale is statistically negligible.

Second, road cars have more than repaid the compliment. On the subject of monocoques, a Lancia Lamba had one almost 40 years before they first appeared in Formula 1. On the braking front, the first cars to use discs were road cars, not racers.

In fact I think that for most of us who drive normal, affordable cars, racing has done rather little. Think of the major road car innovations that have really made a difference to our lives: inertia reel seat-belts, anti-lock brakes and air bags for instance. None of those were seen on race cars first.

For the most part at least the influence of racing cars over normal road cars is limited to advances in electronics, instilling a sense of pride in a workforce and any practical lessons it can learn about being quick to respond to unforeseen circumstances.

So it seems racing is predominately a marketing tool. Should Audi or anyone else be criticised for that? I think not. First this is not exactly a modern phenomenon: the only reason that great pre-war engineer WO Bentley allowed his cars to go racing is that he knew he’d sell more of them if he did. But Audi’s understanding extends somewhat beyond the ‘race on Sunday, sell on Monday’ approach espoused by WO. It knows the value of making a point well and then making it again and again, to a point past where the argument is merely won, to one where the territory is all but owned.

So don’t think for a moment that your next Audi A4 is going to be a better car because Audi steamrollers its way to another Le Mans victory this weekend. But you might still feel that tiny bit better about it anyway. To Audi, that is all the justification it needs.