I wrote a series of liner note bios for a series of European compilations. Unfortunately I never saw the playlists or personnel, otherwise I would have made a lot of corrections for them. Nearly every liner note job I've had has had either spelling mistakes, missing instruments, wrong or missing song titles (like a medley that omits a song), incorrect or missing composers/lyricists in the information provided to me by the label or artist. Since my name is going on the final product, I like everything to be correct.
Of course, if we talk jazz books, no one seems to beat Stuart Nicholson for typos and outright errors.