Originally Posted by 250swb
You understand the reason they are made to focus 'beyond infinity' is because the lens focus ring needs to be customisable from counter clockwise to clockwise in direction
There is no direct coupling between the user focus ring and the helicoid drive/motor - it's fly by wire. Therefore there could be a mechanical or electrical infinity stop or limit on a lens helicoid.
This would still allow the user focus input to be set in either direction with the ring still rotating freely and without a stop even once the lens was at infinity limit.
i.e. the lens could be made not to focus beyond that point even though the user focus input ring still rotated ( in which ever direction you chose in software ;-).
However, it's easier/quicker for a control loop ( AF system ) to overshoot and pull back rather than hit a non-linear hard stop.
Calibration of an electrical infinity point would cost a little extra production/calibration time ( and for most zooms would require a value for each focal length )