Over the last few months, the media have become increasingly critical of Toyota and its handling of the unintended acceleration problem. Recently, Ralph Nader joined the fray, charging that Toyota has lost control of its quality control process. Has it? Or is this problem indicative of a broader, deeper problem in how cars are currently developed, everywhere? Should this problem have been caught during development? The more serious concern could be how well Toyota and other auto makers learn of and fix the problems that customers experience.

Consider a few facts. First off, if the quality control lapse were remotely obvious, Toyota would have quickly pinpointed it once the reports of unintended acceleration started rolling in. They haven’t. First, back in October 2009, they blamed–and recalled–the floormats. Then, in January 2010, they blamed–and recalled–the gas pedal mechanism. Even now some instances and historical overviews indicate that neither of these is the real problem, and that said real problem might be in the software.

So the source of the problem hasn’t been easy to find, even once Toyota was aware of the problem. Discovering it during development, when not aware of the problem and so not looking for its source, would have been highly unlikely.

Second, the problem is rare. About 5,400,000 cars have been recalled for a problem that has been reported about 2,000 times. Even assuming that the problem has occurred ten times for every time that has been reported, we have something that happens in one out of every 250 cars.

To discover this problem, you would need to test several hundred cars, perhaps even several thousand cars. Well, these days all car manufacturers build far fewer physical prototypes than they used to. Much testing that used to occur in the real world now occurs in computer simulations. I doubt anyone still builds even one hundred pre-production “alpha” prototypes. A few dozen, perhaps.

Once production starts a few hundred “pilot” cars are distributed to employees to drive and note any problems. This brings up the third piece of the puzzle: the amount of time the car must be tested before the problem occurs. This clearly isnt a problem that happens every time the car is driven, or even during the first 10,000 miles.

During development, only a small number of prototypes are driven more than a few thousand miles. And hardly any of the pilot build cars accumulate more than a few thousand miles. Compressed development schedules play a role. Led by Toyota, auto makers spend far less time developing a car than they used to. This translates to less time for a problem to appear in a prototype.

Put all of the pieces together, and any problem that strikes a very small percentage of cars after these cars have been on the road for a while is not likely to be discovered during the car’s development.

Of course, there could yet be a smoking gun: it could turn out that someone did notice the unintended acceleration problem within Toyota, and they either decided not to pursue it or tried to pursue it and were blocked by others within the company. But there’s no hint of this yet.

Move beyond product development and Toyota becomes more culpable. The pedal recall includes one five-year-old model, the 2005 Avalon. Some reported cases include 2005 Camrys (though these aren’t included in the pedal recall). Even if a problem that affects a small percentage of cars didn’t pop up during development, it clearly started popping up once hundreds of thousands of cars were in customers’ hands. Dealers must have been aware of multiple cases of unintended acceleration by 2007 or 2008, and perhaps even back in 2005.

What system does Toyota have in place to learn of the problems car owners are experiencing and rapidly develop engineering fixes for them? Judging from responses to TrueDelta’s Car Reliability Survey, Toyota generally does a good job identifying and fixing common problems early in a model’s run. Which is why Toyotas generally continue to perform well in reliability surveys. Common problems are caught and fixed. In this sense, Toyota has not lost control of its quality control.

But the system failed in this case—which notably does not involve a common problem. Why? Does Toyota’s system focus much less attention on rare problems, even if they can result in fatal accidents? Does it track cars less closely after the first year or two of ownership? Either of these could be a contributing factor. But is anyone asking these questions?

These aren’t only questions for Toyota. All car makers should take Toyota’s current predicament as a wakeup call to improve their systems for learning of the rare but potentially fatal problems car owners are experiencing, thoroughly researching these problems, then fixing them.