The positive: POD book publishing gives any independent author the oppourity to print a book (no minimal orders required).
The negative: I've come across many reviews on Amazon from readers complaining about POD books made with cheap paper and poor print quality.
There's also a problem of counterfeit books.
Authors: Lots of authors use services like Gumroad and Leanpub for publishing digital books. Have you found counterfeit POD books of your work?
Readers: Have you ever bought a book to discover it was a counterfeit book? Or if you bought a legitimate POD book, did you notice the print and paper quality?
POD is getting pretty good and it has enabled a great deal of specialty books to stay in print, Princeton and Cambridge have gone heavily into POD and both have good quality, I have a few ~1000 books from them which have held up very well. There is a good amount of garbage quality POD out there from what I have seen, but there is also a good amount of garbage traditional printing out there so I am not sure this means anything, finding well made books is easier for the reader with the traditional options.
I would enjoy finding my books being counterfeited, I doubt I am even on libgen or the like yet. I have never gotten a counterfeited book that I am aware of.
Binding though, is another matter because it is mostly a matter of limiting expectations.