Well, obviously the answer to your question depends on the type of game you are referring to.
On a more professional level, a point guard has to consider what the next move is. In other words, the PG has to have the answer to "Why am I passing this ball to him/her?" clearly defined. If it's a set-offense then it's actually pretty clear, PG passes to X and X does what the predetermined role that the play defines, that could be a quick shot, a dribble in and pass out to the perimeter etc.
But yet again, a good player needs to have a certain awareness of the game as well. Just because the set play is defined to pass the ball out for 3-pointer doesn't mean that you shouldn't consider going to the basket with your drive. So, even though the coach is responsible for the set plays, every player (not only PG) has to have the wits to be able to "bend and reform" the set-offense, when the circumstances call for it.
Another consideration is that during a game, significant portion of the points are scored on fast-breaks. This is especially the case in American basketball vs the European flavour. If you keep that in mind, it becomes even more important to "know" what you are going to do with the ball, that includes "when" to pass and "to whom".
I totally agree with the KYP principle, knowing your teammates is important and in casual games usually underestimated. There I don't only mean what percentage they shoot with, but also in what positions and situations they like to have the ball. Likewise when your teammate has the ball does he drive left or right, does he usually go for the sudden jump-shot or rather push his luck for a layup? These are all great skills for a PG, even when playing for fun with buddies.