I think many of us reading this have had the experience of a computer that freezes or does something we weren't expecting or at the worst time, which throws our concentration. We have become used to odd glitches in cars that puts it into creep home mode, but when it's hooked up to the diagnostic unit there's no record of a fault. It's these sorts of incidents that has given most of real scepticism about the reliability of computer controlled systems. And yet I doubt if any reader could hold up their hand and tell us they've never had a piece of computer technology that's never let them down. - Or could they?
In reality I doubt we are ever fully aware of all the systems we use that rely on some sort of computer or electronic wizardry as part of their control. If a system quietly gets on with what it's supposed to do it doesn't draw attention to the fact it's working properly, so well designed and reliable kit just doesn't get noticed.
That's fine for those items where a failure would be easily detected before a dangerous situation arises, but then we come to those device which are there as a safety net of some kind. ABS braking, air bags, Electronic Stability Control, ATC for trailers etc. These systems are normally dormant until they are needed, by which time it may be too late to recover a situation by other means. In these cases there is always that nagging doubt they will be there when you need them. The best the manufacturers can do is design them to do a self test when you turn on the ignition. But how do you know that self test is adequate to confirm the device will deploy properly under duress?
The fact is there is no electronic component that can be guaranteed to be 100% reliable. Mean time before failure (MTBF) rates can be up in the hundreds of thousands of hours but those are averaged and statistically derived figures and it actually means that a very few components may fail almost immediately, the bulk will survive for the stated MTBF and some will dramatically exceed the MTBF. The problem is you cannot know the life of every component used in your car - and you may be unlucky and get one with a short life.
Then we come to the software needed to enable the computers to do their job. Is it capable of distinguishing the difference between a car approaching on the other side of the road, or the gap closing between you and the car in front before applying the brakes?
The buying public are in no position to evaluate the manufactures development systems. WE do have BS/EU standards relating to the development of safety critical software and systems and we have to hope they are robust enough to ensure conforming designs will be functional and reliable. We also have to trust the manufacturers do use all the necessary techniques to design test validate and verify the safety of software and components.
But there will always be that nagging doubt......(Dare I mention VW and emmisions)