nowadays, as there are less and less proofreaders at many publishing houses ("downsizing" has hit this aspect of the field quite severely), a lot of things which before would have been caught simply aren't, as there is no one to catch them.
I'm pretty sure proofreaders == 0 at some publishing houses now. I will probably buy
The Collected Stories of Carol Emshwiller Volume Two, only because I already bought
Volume One, but it's the very worst proofread book I have ever seen (depending on how you compare the larger scale hackery inflicted on Asher's
The Engineer Reconditioned by Cosmos) and I will never buy any other from them. Non-Stop Press needs to stop and correct some typos. The errors are fairly consistent but I only wrote down the ones on the 14 pages from p.25-39 (thinking to apprise the editor/publisher of them) and there were
18+ typos (the '+' because sometimes multiple errors will occur on the same paragraph or even line). Worse, they are usually "Eye half a spellchecker" sorts of errors which makes for sentences of complete nonsense rather than an honestly typo'ed word that could easily be mentally corrected.
But, yeah, it's a general problem.
And this is after years of the internet have blunted my own proofreading abilities. Who knows how many errors there actually are?
(To digress, this another reason why ebooks are so dumb: I'm to pay money for a nocover book and, not only that, but a nocover book that hasn't been proofread? At least, in theory, you could edit your own ebook to correct these sorts of things, though I wouldn't be surprised if you couldn't. But then I'm paying
them for
my labor. (This all vis a vis the publisher, not the author.))