A POS-based bar code symbol reading system that reads bar code symbols on objects being passed through the 3D imaging or scanning volume supported by the system, and employs one or more object motion sensors (e.g. imaging based, IR Pulse-Doppler LIDAR-based, ultra-sonic energy based, etc.) to (i) measure or estimate the speed of objects being manually passed through the 3D imaging or scanning volume by the system operator, and (ii) visually and/or audibly display object scanning speed measures or estimates to provide the system operator with feedback for optimizing system throughput. The POS-based bar code symbol reading system has a performance advantage that leads to quicker customer checkout times and productivity gain that cannot be matched by the conventional bar code symbol scanning technology.