I'm not really willing to be drawn into this but, for what it's worth, here's my take. Almost every product will have a number of models that will be susceptible to faults. This is true of everything from computers and phones to cars and soap dispensers. Ultimately, the larger the production run the mirror these faulty models there are likely to be. For example, in two weeks my wife has had to have her iPhone 4S replaced 3 times. I have had one since the day they came out and have never had a problem. The thing about items such as cars, is that there are a greater number of components and parts that are coming together from a number of manufacturing points. Each individual part has the potential to be faulty or substandard. When these are combined, these can produce a lemon. Ultimately, for new car owners, these individual cars are untested and we are running them in and are unfortunate to be the ones that discover any flaws. I have had a number of faults with my car but these have all been rectified by Peugeot but have not been severe enough to require the car to be replaced.
However, one thing I cannot understand (and I'm not referring to Peugeot here) is why we, as car owners, accept a "whole" product being continually repaired or fixed. In these rare instances that a car suffers from a litany of continual problems surely we have every right to take the car back and demand a refund. You would do it with almost anything else. If my microwave was faulty and kept going wrong I would demand a replacement or refund. Why not with a car? Consumer protection states that an item must be covered by the manufacturer for the duration of what is an acceptable working life for that product. A TV might have an average of say 5-7 years. Should it be faulty, although people rarely challenge this, it should be replaced or refunded by then manufacturer even if it is outside of the warranty which may be, for arguments sake, 2-3 years. Hence the reason that extended warranties are a con. So, this begs the question, what is the average working expectancy of a car, 12 - 15 years, 200,000 miles? I don't know and don't profess to have the answer but ultimately my point is this, why don't we demand a replacement or refund if the car is substandard?! I would suggest that, should a car suddenly have a range of problems at any time, aside from expected wear and tear of a part, why don't we, as consumers stand up for ourselves and demand better. Should this happen I would expect ALL car manufacturers to go to much greater lengths to test all parts and all vehicles.