It turns out, if you both meet the success and failure condition for a quest simultaneously, you fail the quest. Also, quests appear to only be checked at the end of the turn. For instance, from my last game: I got the "Build libraries!" quest. It wanted me to build 7 libraries before Ren era. I already HAD 7 libraries. I was also 1 turn from Education. Hitting "end turn" I immediately failed the quest for finishing Education, which advances you to the Ren era. Reloading and switching to another tech for 1 turn caused me to successfully complete the quest because I already had the 7 libraries. Either way I had to wait until end of turn for the check to complete the quest. I guess my complaint is that I had completed the quest before the Ren era, so I was a touch annoyed that I didn't receive credit. I guess I can see it going either way when you actually build the 7th library at the same time as finishing the tech. Is it possible to reverse the order of these checks, and if so, do people think it should be done, or do they not really care?