I went looking for childrens books. Some titles looked good. But if you view the preview .... complete trash. Must cost nothing to upload, and you might get some suckers that don't realize.
Part of the issue is print-on-demand and drop shipping. In the old days, you had to stock and distribute inventory as well as do large-batch printing runs in order to get books out at a price and delay acceptable to consumers. This is in short why publishers exist - to identify potential quality products and take on the financial risk of generating an inventory to sell.
The modern structure pioneered by Amazon removes all that. The actual cost for a seller to make a listing is apparently half a cent per month. After the first 100,000 listings, that is, and only on SKUs without a sale in the last year.
