Because it might lead to even more savescumming, is why.Even if save scumming is that a big problem, you can random generate a "seed" and you will always roll "X", doesn't matter how much you reload. IDK why few games uses it....
Say: you have two targets. You are going to miss two of them even if standing 1/2/3 tile closer to them. but if you change to another tile and shoot one, you are going to miss him but hit the other. Thus this is the optimal step you are going to choose. All this require is ten reloads.
Use a separate seed for each NPC and for each skill check at the start of the game.