You buy something, drawn by its promised ability to recognize human commands, and it just doesn't work well enough to bother with. (scientificamerican.com)
Part of the reason behind this could be that dogs have been bred to respond to human commands whereas cats never needed to learn to obey us. (mnn.com)
These are all destined to perish with use, because they are based on HUMAN COMMANDS AND TEACHINGS. (nakedpastor.com)