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This question asks why isn't the Force used to snap a neck instead of choking. It is harder to snap a neck than to hold someone, so it kinda makes sense that it's not used often.
However, snapping a neck is a very ineffective way of killing if we have a ranged attack that can't be covered. Why not use the Force to pop a vein inside the person's brain? Just scramble a part of the brain and the person is gone. Not much strength is needed, the kill is instant (so you can't really prepare for it).
Why not just cause a stroke to an enemy?