Something frictional games should do in next games.

[Spooder Wekd]

I know what I said, its not down to AI its more on the source code, but its mainly down to level design as well

and AI isn't the only code controlling NPC's and AI would only dictate if its chasing the player or not... not actually control where the monster comes from

I mean level designs they would have to compensate and add spawn locations and a previous room for them to spawn from, or are they just going not fade in next to the player?

Dude, STOP! You lost. AI is ANY CODE THAT CONTROLS NPCs. It is not just some function hidden away. As you describe it "just whether its chasing you or not" that is one variable, an if statement, and a path finding algorithm (with some other stuff I wont get into) AI is more than that, going through a door can be done in code, the whole thing is the source code, even the AI! No spawn point is needed, just use the door's X, Y, and Z values to set an object of the appropriate class. You have no damned idea what you are talking about.

Edit: You do not design games, if you do, you DEFINITELY are not a coder.