/jp/ - Otaku Culture

>>9078838

Because that wins you ONE battle in a fight with SIX opponents, and Command Spells are more for emergency unforeseen consequences (ambushed by enemy magus, Servant about to be destroyed by noble phantasm, etc).
Furthermore, if it was Lancer, a "fatal wound" doesn't stop him from acting for a very short while and attaining a double knock out. Even worse if it were someone like Mordred, who literally killed Arturia with a strike after he was already dead.
Oh, and using the third one means your Servant is free to fuck off somewhere else, or just not listen to you in general if they're not the type to betray.
In short, you have no idea how to allocate vital resources.