What causes more defects in old electronic devices (the 90's and 2000's) when they remain stored for a long time without being used are the electrolytic capacitors? many people report that after a while stopped when turning them on there is no sign of life
Interesting topic. One thing I do know, wet slug Tantalum capacitors need to be used regularly, or the dielectric breaks down. the worst thing is to use some gear with this capacitor type for a while, then put it in storage for several years, maybe even a decade, and then power it back on. The caps will short out, and if enough supply current is available, they will catch fire!
I have a pick and place machine made in about 2000. I got it from an auction in Austin, TX in 2020. Looking at file dates on the disk, it apparently was used between 2001 and 2004, and then abandoned after monkeys broke it. So, apparently it sat in unconditioned spaces from 2004-2020.
I have had a huge number of problems with this machine, mostly looks like the failure of ICs with flash/EPROM memory. I'm guessing that storage in high temperatures/humidity caused early failure of these parts. None of the used parts I have put in it have failed.
Jon