Tin whiskers are what mysteriously grow out of electronic parts that don't have enough lead in them to stop the problem. When these grow, they start shorting out circuits and causing all sorts of intermittent and permanent weird problems.
Solder is the soft white metal that holds all the parts together on circuit boards. Military and space electronics require at least 3% lead in their solder for precisely this reason. Normal solder is 40% lead, but optional RoHS proposals (that's the little "10" in circles on Nikon lenses and other products) demand no lead.
Consumer products makers love the RoHS/no lead standards, because these whiskers ensure that consumer electronics made without lead will all die in about ten years, so no one will get away with using old products, and have to keep buying new ones.
10 years is a perfect target life: it's long enough that no one blames the makers for deliberately building this in, and long enough that the maker has no warranty or good will problems. "Hey, it was ten years old, what do you expect?" Hey, I have plenty of thirty-year old and older audio and video products working here just perfectly, thank you.
If we all have to replace everything after 10 years, that's a lot of TVs sold. I have a two Visio TVs, a crappy brand, that died on me at 1 year and four years.
Reading the NASA paper, it may be a lot less than 10 years. All AF lenses work with electronics; they have been loaded with circuit boards and microprocessors and memory since the 1980s. Lose a circuit, and even a lens becomes useless.
No one ever died when their lens died, but the news media, sponsored by car ads, certainly doesn't want anyone learning what caused the Toyota unintended acceleration (UA) problems. Toyotas, like most modern cars, are drive-by-wire. Your gas pedal is nothing more than an input to a computer. Cars haven't had gas pedals connected to throttle valves since the 1980s. Toyotas use a variable resistor to encode gas pedal position, and feed that to the computer that does some math, and then controls the fuel injection and air induction systems itself for optimum efficiency.
The unintended accelerations were caused when a tin whisker in the throttle pedal encoder shorted it to make it seem as if the pedal was pushed all the way down!
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