It depends on the circumstances, but in the UK and most of Europe, consumer rights are much stronger than in some other parts of the world.

Here in the UK, the basic rule is that the vendor who sold a product to a private individual is on the hook for anything that goes wrong -- that is, they can't just pass the buck to a manufacturer under warranty or some other fall guy, they have to deal with the problem or be held responsible. Whether the vendor can in turn recover any losses from the manufacturer or reseller who supplied them is then that vendor's problem, not the end customer's.

Usually if a product is defective, the next step will be to repair, replace or refund. The legal position tends to be based on both sides being reasonable. For example, if you have a product that fails earlier than you might reasonably expect but still after a couple of years of use, you might get a refund for part of the original purchase price but you probably wouldn't be entitled to all of it. On the other hand, if a product fails in the first few months and the vendor can't repair or replace it, you're probably entitled to a full refund and there is a presumption that the product was defective unless the vendor can prove otherwise. In some cases, rights to a partial refund might last as long as 6 years, if the product purchased might reasonably be expected to last that long but that one didn't.

Several other shenanigans that vendors try to pull elsewhere also don't hold up here. You can't rely on dubious arbitration terms in sale contracts to override statutory consumer rights. A vendor also must not mislead consumers over their rights, for example putting up a sign saying "no refunds" when the buyer might have a legal right to a refund for a defective product. In fact, it's actually illegal for merchants to mislead in that kind of way, which is why you'll see often notices up at the tills that say something like "your statutory rights are not affected" to make it clear that they're not trying to illegally misrepresent anything about those rights.

This is all in addition to any more generous policy a merchant might voluntarily offer or any warranty a manufacturer might offer on its products regardless of where someone buys them.