Twelve Reasons Why Things Don't Sell

I was brainstorming on why things don't sell. I'm not stressing about it, it's just one of those undefined, nebulous areas in retail.

1. They don't want it. An obvious answer. It might not interest them, but it might also lack quality. Many good RPG books have poor artwork that turns off a lot of people.
2. They already have it. It might be a great product, but they might have bought it online. They might have forsworn print products for PDF. They may have bought it at a convention or received it as a gift.
3. It's damaged. It might be shelfworn. Parts might look damaged. Some miniatures have flash that the uninitiated consider to be damage. Bent weapons are treated the same way.
4. It's too expensive. Many games can't be sold at any price, but many games start to zip off the discount shelves when the price is reduced. Good games, priced wrong, eventually move.
5. They can't afford it. Oh, the many things I wanted for D&D when I was 12.
   
6. It's sequentially undesirable. It might be book two, while book one is out of print. Many RPG systems will grind to a halt when the core book is missing.
7. It's an old version. Old RPG books might still have value, while old codices for miniature games tend to have little to offer.
8. Market saturation. You've simply sold the item to everyone who could possibly want one in your area. This is why conventions are such great venues for remainder product.
9. Undesirable color. Yellow and brown dice, orange card sleeves, and certain shades of paint sell poorly. We have some shades of paint that are very close to another shade that have sold maybe one a year, compared to 3-4 of the popular shade.
10. They can't find it! A great way to boost sales without buying inventory is to re-arrange the shelves. Games that are faced, sell better than games that are spine out. Rotate the faced games and sales might increase. Also, there's always a couple of areas of the store that are ghettoized, sub-optimal places for shopping.
11. Staff issues. The game is great, the price is right, the staff treated the customer poorly.
12. Environment. The store is dark, smelly, crowded with people or product. The music is too loud or just the wrong music. The other customers are intimidating or obnoxious.
    

Can you think of any more?