Someone would have to cut the spot you choose quite deeply. Exactly how deep depends on the person—you've got to get past the skin, the subcutaneous fat, and into the underlying muscle, and since everyone's muscle-to-fat ratio is different, there's no one-size-fits-all depth. The real barrier is the muscle itself: you're slicing through layers of tissue and small blood vessels before you even reach the larger vessels
Arteries lie even deeper, shielded by thick muscle and connective tissue. Most deaths attributed to "cutting an artery" without a sharp blade actually happen because the vessel gets compressed—like when someone hangs themselves, the noose tightens around the neck muscles and presses down on the carotid arteries and jugular veins, or in combat when a chokehold compresses those same vessels. Crushing the arteries against the spine or between muscle and bone is far easier (and faster) than slicing cleanly through muscle to sever them. If you tried to hack through that tissue without anesthetic—or some strong narcotic—you'd endure excruciating pain
Even the CIA's harshest interrogation manuals steer clear of bloodletting methods like this. It's slow, unreliable, and risks prolonged suffering plus uncontrollable bleeding. In practice, agencies have preferred techniques that incapacitate or extract information more quickly and predictably than manual arterial cutting