New equipment and machinery of most kinds can deteriorate if left unused for many years, even in original packing. This is why there are recognised methods for "moth-balling" plant, equipment and scientific instruments which will not be used for some time.
The sellers description was very brief and uniformative, and, had I been seriously interested in bidding, I would have asked quite a lot of questions, or, ideally, tried to inspect the item is it were within a accessable distance.
I've had some good bargains from Ebay, but common sense is needed, especially if you're spending a lot of money. And also, of course, it's best to set yourself a firm limit at the start of what the item is worth to you.