Attack of Opportunity question

[Siuis]

If a PC just runs out of combat, they're doing so recklessly, which provokes AoO's. It does not matter if they attack or do not attack during that round.

this is wrong.

If you Withdraw (do nothing but retreat from an opponent) then the square you start in does not count as threatened. This is technically different than a five foot step.

In a combat situation, this makes more sense than you'd think. To move, strin a bow and aim, then fire requires a lot more coordination (and taking your eyes off of your opponent) than keeping an eye on them, stepping back, and anticipating their swing so you can avoid giving them an opening.