How does Amazon prevent defective products from being swapped?

Example:

My Playstation has broken down, I buy a new one at Amazon and send the old back and pretend that was broken by Amazon.

How does Amazon prevent that? Of course a 2 years old Playstation would be recognized, but a relative new one?

I do not want that, it's pure interest.

Actually, you have a serial number for each device. Now I do not know how it is at Amazon when they receive a delivery of goods. Whether there's also the serial number on the documents.

Unfortunately, not even in used items, it happens again and again that these have a defect but amazon refunded this always immediately but it should be noticed that you often buy things and send back you will check the serial numbers

This is not checked.

We can only ask you to refrain from doing so, but that is undetectable.

For example, if you have a Playstation with an expired warranty at home, you could buy a new one from Amazon and return the old one, even though it no longer has a warranty because returns are only sampled and you can't prove the difference.

I hope that has contributed to the clarification.

So you do not have to be ashamed if you implement your idea, because that's a good idea, so to speak.