Many humans do not use what they have. Intelligence is meant to steer the mind, discern that which is worth pursuing or acting upon, and that which is not. The mind comes up with a gazillion propositions, thoughts, desires etc and the intelligence is supposed to pick and choose wisely, based on ethics, wisdom, beliefs, conscience, etc.
No machine or stone or any non-living ie non-conscious thing can do that.
As I heard once, the mind produces thoughts as the kidneys produce urine.