The acronym is similar to "F.A.Q.".
The problem with "F.A.Q." is that the questions are rarely actually "frequently" asked. Hence why people should use "P.A.Q." instead.
Q. I was just wondering why you decided to make an urban dictionary write up about "P.A.Q." on the 20th of March, 2008.
A. It is because questions like the above one are OBVIOUSLY not asked frequently.