Heck, even 5 years?
All of this for some cheap widget? (I assume from your description it's cheap).
If you can find a single case (or similar case) where this happened, I will stand corrected.
If this was a $2000 laptop, I can absolutely see that - e.g. Apple Macbooks in Australia have a statutory warranty longer than the manufacturer's 1 year warranty. But I think you'd be hard pressed trying to claim after 3-4 years that it should still apply there. And this is for a $2000 laptop.
Here's an example of how it often works in practice, although on a shorter timescale: http://forums.pepipoo.com/index.php?showtopic=52242
Laptop power socket fails within 6 months. Is repaired, fails again. Demands refund, is refused. Takes company to small claims court; they fail to mount an effective defence and are in any case in the wrong, so he wins £400+costs.
Not exactly; in the UK it's tied to "reasonable expectations" for that kind of product. Certainly non-smart heating controllers would have an expected life time of 10-20 years, so why do the more expensive smart ones get away with a lifetime of less than 3?