If you’ve just bought a Mini featuring one of the recently revised petrol engines, or a Ford Mondeo with the new Ecoboost power unit, you might have been more than a bit miffed to discover that, a few months after you bought your shiny new upgraded car, it has been rendered obsolete by another round of upgrades.

Read Autocar's first drive of the new Ford Mondeo

Take the Mini. In March this year its range of petrol engines were improved, the 1.6 litre engine of the First, One, Cooper and Cooper S all putting out more torque, and in most cases more power, together with improved economy.

These improved Minis were announced in January and went on sale in March but for some reason were not launched to the press until the beginning of June.

With the burst of publicity that followed it was easy to conclude that they were 2011 model year cars, encouraging buyers to jump in. But the 10,628 individuals who bought one of these cars are now discovering that it’s already obsolete, because the actual 2011 model year cars, which get a light detail exterior refresh, some useful interior upgrades and new diesels, are on sale now.

Mini is not alone in upgrading its models piecemeal. On June 11th, Ford announced the arrival of the new 200bhp Ecoboost Mondeo and some upgraded 2.0 TDCi diesel models, together with a new 161bhp version of that engine.

To its credit it announced the imminent arrival of the lightly facelifted 2011 model year Mondeo a fortnight later, which was unveiled at the Moscow Motor Show late last month, these upgrades rendering the Ecoboost and diesel models announced a fortnight earlier obsolete.

So there was a warning, though not every Ecoboost and 2.0 diesel buyer would have seen it. Ford explains that: “We introduced the first changes to media and public at Goodwood's 2010 Moving Motor Show in July, but in view of a media event in Europe we felt we should also communicate the same news here in the UK to give customers the fullest possible picture.

“The process of continuously improving vehicles and launching the results inevitably creates a dynamic automotive marketplace, which Ford has led in the UK for almost 35 years.” Mini declined to comment on its launch plans. 

There’s nothing new about piecemeal model improvements, and we’re obviously in favour of manufacturers upgrading their products, but it would be a lot better if these upgrades avoided the production of a bunch of interim models with a life-span of months.

Cars may be fast moving objects and consumer goods, but they are not Fast Moving Consumer Goods like washing powder or breakfast cereals. On the other hand, we’re now very used to MP3 players, computers, phones and TVs being upgraded or replaced every few months.

So what do you reckon? Are these quick-fire, staged upgrades just fine, or would you prefer an annual round of autumn improvements that bundled everything up in one go?