How a stick can report movement while standing still
A Joy-Con stick does not send the console a picture of where it is pointing. Inside the stick assembly, small electrical contacts slide across resistive tracks as the stick tilts. The changing electrical signal tells the Switch how far and in which direction the stick has moved.
Those contacts press against the tracks every time the stick is used. Repeated motion can wear the contact surfaces and leave fine debris inside the assembly. If the electrical connection becomes uneven, the signal may fluctuate even when the stick is centered. The console reads that fluctuation as a real input, so a character may walk or a menu cursor may creep without anyone touching the controller.
Why the problem can grow over time
The stick’s center is not simply a fixed mechanical stop: the console relies on the sensor’s electrical reading to identify the neutral position. Wear that changes the reading can therefore make “resting” look slightly off-center. Calibration may adjust how the console interprets the signal, but it cannot restore a worn contact surface.
That is why drift can return or persist after a temporary fix. The visible symptom is a wandering cursor; the underlying problem may be inside the small sensor where each tilt has gradually changed the path the electrical contact travels.
