Speaking as a working novelist (who has been earning a living that way for the past 19 years, thank you very much) I note that the editor quoted above was speaking of print sales, not sales including ebooks. A really prominent feature of the publishing landscape in the past decade has been the collapse of the mass market distribution channel -- small C-format paperbacks which are sold on 90 day credit: when payment is due the distributor must be paid in full or receive proof of destruction in the form of stripped covers. (This channel was originally created for periodicals and expanded to books in the wake of the depression and the second world war. Trade books sometimes come in C-format -- especially in countries like the UK where the mass market channel crashed and burned in the 1990s -- but usually come in hardcover and A-format or B-format: larger paperbacks. These books are returned intact to the distributor for credit, and a lot of bookstores rotate their stock on a 90 day basis, relying on the wholesaler's line of credit to cover their expenses.)
Anyway: mass market paperback sales in the midlist (not the bestsellers: the other 90% of the trade) fell off a cliff once ebooks showed up. Ebooks were about 1% of my sales in 2005, rose to about 5% by 2008, then took off like a rocket: I'm now with a publisher who prioritises ebooks (but issues hardcovers as well), with roughly 50-60% electronic sales. In contrast, the figures for my mass market paperback releases dropped from roughly 60,000 for my first novel, to under 10,000 a decade late ... although I'm earning about five times as much.
I have two hypotheses to explain this:
1. MMPBs were traditionally bought as disposable reading: the vast majority of customers wanted a cheap read, and binned/donated/re-sold their MMPBs on the second hand market after one read. (Hardcovers, in contrast, tend to be collected by fans.) Ebooks fill the disposable reading niche even better than MMPBs insofar as they're infinitely more portable, and these days you don't need a specialized gadget to read them: any modern smartphone will do.
(It's no coincidence that my rising ebook revenue took up the slack from my descending mass market paperback revenue.)
2. Amazon, the 500kg gorilla in the ebook field, doesn't release any figures for direct sales of self-published ebooks, but I'm guessing they're huge. A lot of writers bypass the traditional publishers completely and go direct to ebook via Amazon, who don't offer the range of support services of a Big Five outfit but who also pass more of the money through to the author. (Disclaimer: I'm with two Big Five publishers. The higher royalties would be nice but I don't like having to recruit and pay my own editors and proofreaders and typesetter, and I want to spend my time writing rather than being a one-man publishing business. There's this thing called division of labour ...) Anyway: about 90% of the self-published material (my opinion is based on a three year deep dive into Kindle Unlimited) is rubbish that, frankly, isn't ready for publication ... another 9% is decent commercial-grade fiction, and 1% is stand-out star quality stuff, and some of that is going bestseller under the radar. That is: because it's sold on Amazon and AMZN doesn't feed numbers to Bookscan AIUI (Bookscan captures retail sales at the EPOS terminal) they don't show up in the charts, even if they sell a million copies. And these books are invisibly eating away at the major publishers' market, corroding it below the waterline.
I have a huge collection of C format paperbacks from the 1960s and 1970s; as ephemeral as these are supposed to be, they held up really well until about 2005, by 2015 the yellowing started getting serious.
I (mostly) hate larger format paperbacks, since these are often poorly made -- you bring a $50 book home, open it, and the spine breaks right away.
The conventional wisdom that hardcovers are "better" than paperbacks seem to be belied by the fact that hardcovers are usually cheaper on the secondary market, sometimes by a little, sometimes by a lot.
US hardcovers are supposed to be saddle-stitched and bound, and printed on acid-free paper. UK hardcovers use cheaper paper and perfect binding, as do paperbacks; "perfect" binding is basically cut sheets held together using a thermosetting glue. A lot of late 60s/early 70s UK paperbacks had such terrible glue that they were cracking and the pages falling out within a couple of years.
But "bookmark can't fall out accidentally" and "can read in poor lighting conditions" are right up there, too.
I never treated paperback books as 1-time-use items, but I was also more choosy about what books I bought because I didn't have much money. (And continue that trend today, now that I do have money.) I am more likely to buy digital books on a whim, though, especially if they're cheap enough.
Like you said - 90% of self-published is rubbish so it makes sense that big players like Costco etc would use the Big Five to filter..but other than getting that intro, what else does the Big Five provide?
Also - shameless plug for her book, STEM-Land: The Noble Gases Come to the Rescue. It's basically Pokemon w/ the Periodic Table, so it's for kids but I happen to think it's great.
(but I am happy to say that I own a physical copy of the full laundry files)
for a while i was very much into ebooks for many of the reasons others on this thread have sited, but eventually started purchasing physical copies again. part of this was uncovering a well-worn copy of Dune in a box. it was printed sometime in the early 1970's and everything from the cracked spine to the yellowed pages to the "sale, 10¢" written in a flowing script the inside cover brings a nostalgic value i couldnt possible replicate with an ebook (for painfully obvious reasons). furthermore, on uncovering this book i found the bookmark to be the receipt from the bookstore that i purchased it from a decade ago. other books on my shelf contain similar personal items such as a postcard welcoming my daughter to kindergarten, a $1 silver certificate i found in my change years ago, a receipt from a store that i used to frequent as a teenager whose proprietor has since passed away...
: correcting a typo
I guess its no wonder that book publishers are terrible at developing great authors.
Think PoC || GTFO bibles. My staff thought it was crazy to publish them. Haha.
The Big Five are all about supply chain management contracts. That's all. Everything that can be outsourced is outsourced.
But this leaves them vulnerable to obsolescent boilerplate contracts horked up by an ossified legal department, which get in the way of business innovation.
Some of them are working around this, either by firing off contract updates for backlist titles to be signed by their authors or assignees: others by incubating internal startup ventures with from-scratch redesign of their workflow.
Example: Tor.com is an imprint of Macmillan, and its chief executive is Fritz Foy. It goes back about a decade and its front end is a very successful SF/F media website. Tor is also an imprint of Macmillan, and its chief executive is Fritz Foy. It goes back about 40 years and its website is ... not its best aspect. In fact, Tor.com's entire editorial staff also wear Tor hats from time to time, although their marketing team are different. But the contracts might as well come from another star system. Tor's legalese focusses on the traditional trade fiction distribution channels and would you please sign this paragraph about microfiche and gramophone rights just in case we still use those formats, while Tor.com assumes ebooks have priority and by the way there'll be a hardcover issued via Tor as a distributor, and maybe a trade paperback.)
Some of the big five have roots going back to 1894, and earlier.
(Time runs at a different pace in publishing, if that makes sense.)