You're right. No book is perfect. (That's why I'm afraid to open the covers of mine now!
Fact checking is generally up to the author, since no publishing house carries experts in every field. Typos, sentences, structure and flow are supposed to be attended to by the editor(s) the publisher employs (one reason for the publisher's hefty cut, often 40% of cover price, after selling the books at 60% discount to wholesaler; then paying the royalties to the author).
The difference with this project is the sheer volume of errors both English and factual in edition 1. They seem far reduced in ed. 2. We're really rooting for volume two now.