Most of the problems that have happened with Pathfinder FAQ are due to a FAQ being answered on a certain context and affecting another rule outside of that context. This has happened quite a few (noticeable) times, which also has reduced the number of FAQs produced by the developer team for that very same reason.
The way that questions are picked to be answered is vastly different, where the community vote for the questions, the developers sit around a table and discuss between them how to answer that question or solve that problem. When a problem has no easy answer, the developers do not answer it and go for the next question. Sometime later (maybe years) they will have an answer for it that will actually fix the problem. But there are questions that remain unclear for a long time.
But a great point that saves Pathfinder's FAQ from the same destiny of 3.5's FAQ is the fact that many of those rulings are actually printed on future editions of those books. Some have slipped through, so I won't say that they always do this, but when they see that they have to change a ruling, that is usually reflected in the next printing. This blog post actually describes the process of FAQ answering.
Until the PaizoCon of each year (usually May or July), they try to post weekly or biweekly updates on FAQs, which greatly motivates people to keep voting for questions to be answered. But from the weeks before PaizoCon and a little after, and once again until before and after the GenCon (usually August) of the same year, the FAQs slow down a lot due to all the events, planning for the next year releases and holidays. They practically return to (semi) normal schedule around October or November and pause again in December. So you could say that new FAQs are posted frequently for the first half of a year, and slowing down considerably for the remaining half.
If you want to keep track of new FAQs, you can always mark this thread as a favourite and you will be notified when they update the FAQ.
(Note: Starfinder has reduced this a lot this year, but I hope they pick up their pace again.)
For Society play, those same rulings are incorporated by the coordinators, regardless if they are in print or not, and the official document (in pdf and available for download) is often updated (every few months)
On the other hand, the developers are usually allowed to give their personal opinions on how certain rules should work. This either has caused problems or actually led them to take a look at certain questions that deserved an answer. Most notably, Mark Seifter (Designer) and James Jacobs (Creative Diretor), have known threads to ask all sort of questions there. Those are useful sources of rules as intended and also a door to point them to questions that could obtain an easy answer, like those from newly released books. Ironically, Jason Bulhman (Lead Designer) personal thread actually says to ask "non-rules questions" to avoid the problems I mentioned.