A product sale depends on the demand (or interest) for a specific product and its asking price. For example. my MSB Premier DAC sold in 2 hours after it was posted for its asking price
And, yes, I have one item that has been listed for 5+ months. I substantially lowered the price and still no sale. It is listed for a third of its asking price and still has not sold. Obviously, no demand for this product meaning no sale.