It also reduces mistakes in picking. It's hard to grab a size medium T-Shirt from the shelf above the larges by mistake if the shelf above the larges has lipstick and spark plug wires on it.

I don't understand this.

You have a product with a UPC. You have a picker with a UPC and a scanner. If the scanner scans the wrong UPC, the picker grabbed the wrong thing.

And yet I get sent the wrong item from Amazon multiple times per year. Ballpark of 1 in 20 orders. And not like I got the wrong order. More like I ordered spicy taco seasoning and receive regular taco seasoning. So a mistake that makes sense if you were matching on titles but why not match on UPCs?

Wow this is one of the most elegant and interesting things I've read in a while. This is absolutely genius. Amazing!