The final days sales leading to the sclosure of a store can tell you plenty about the products you have been offering. I know for personal experience.
Right now, in the US, this is on show at the Papyrus card and gift stores, which will all close on February 26. They have been running a massive sale for more than two weeks. What is left is what has not worked for them. I say this given that everything is discounted by between 50% and 75%.
On the card shelves there are captions that remain quite full. 10 cards for $5.00 is a good price as most of these cards regularly sell at $5.99 or thereabouts.
Still, plenty of greeting cards are unsold with less than 3 days remaining.
What has clearly been a failure at Papyrus is their wooden models. These are small battery operated merry-go-rounds and similar. Several stores I have seen have windows full of this stock. Given that Papyrus has stocked them for several years I am surprised their sales data did not forecast problems with the category.
Retail success comes down to giving customers you can reach what they want and operating with a cost base that permits profitability.