JayCar Electronics had a warehouse clearout sale here in New Zealand last year, and if you've seen Dave's videos about JayCar warehouse sales, you'll know what it was like: huge amounts of unsold/faulty/returned goods on sale for cheap. I was in early and got hold of a pallet of mostly 1kW sine wave inverters for only a couple of hundred bucks - all marked as faulty of course, presumably customer returns.
Looking through them yielded a few quick insights. On one unit, the return note suggested that someone had tried to use it to start a big pump and returned it because it hadn't done the job. There was nothing wrong with the inverter at all.
However the most remarkable thing was that probably 70-80% of the units had one particular fault: the mains output socket was broken so you couldn't plug anything in. It was just a bit of broken plastic, so the part that holds the contacts had fallen away from the front faceplate. Obviously a weak part, some sort of design/manufacturing error. So tens of inverters got binned, each worth hundreds of $$ - and the only fault was a $5 output socket being broken, the inverters themselves were still working! Many of the faulty units looked brand new, still in the boxes with all their accessories, so they must have been dead on arrival or just a bad batch. What surprises me about this case is not just the cheapness of the failed part, but the number of failed units, and the simplicity of the fault, and thus how easy it is to diagnose and repair. You literally don't even have to open the units to work out what is going on. One diagnosis and one box of replacement parts would've enabled the straightforward repair of thousands of dollars worth of stock. It's possible someone did realise this but liability or company policy got in the way of fixing and re-selling them. Either way it's kind of sad.
And it makes me feel like such a scalper to make a profit from this!
But the alternative is them going to landfill, and nobody wins in that case.