And, to be even more clear, I wasn't referring to simple word typos and gramatical errors. I was asking about content errata. That seems to pop up as a problem with a lot of games.
Depending on the game and audience, there seems to be an acceptance of it as inevitable and no big deal, so it's going to end up low on the totem pole. When it comes time to meet those deadlines and dates given in advance to distributors, it's often a rush job or not done at all.
At the same time, if it's a priority to the creators, it shows in the end result. If you look at a game like
Disapora, it was virtually perfect in its first printing, because those guys are absolute wonks about it (along with typography and layout). On the flip side, WotC reprinted D&D4E as "deluxe editions", and didn't even bother to correct the errata they knew about. At the end of the day, they know that their market accepts it, expects it and will buy anyway. Actually, it sounds like the videogame industry, deciding that it's okay to "go gold" when it isn't, and fix it weeks later with downloads. Or not.
The level of errata we see in gaming would never stand in other markets, like textbooks or technical manuals. It would hit them in the pocketbook. As long as it doesn't in the RPG market, there's no incentive to make it a priority unless the creators already feel it is.
What seems most strange to me that most publishers won't even bother to update PDFs with fixed material or errata added, even though the industry used to pimp it as one of the huge advantages of moving to the electronic format.