Intentional imperfection separates man from machine.
People commonly ask "Will artificial intelligence ever catch up to human intelligence?" Well, we will allegedly be able to reverse engineer a human brain by 2030. http://www.wired.com/gadgetlab/2010/08/reverse-engineering-brain-kurzweil/ Though, does this qualify as artificial intelligence? Reverse engineering a brain is simply synthetically creating human intelligence.
I believe what separates human intelligence from artificial intelligence is that we intentionally "malfunction". We know what is best for us, or what "we are programmed to do", but we freely disobey our bodily instinct and intuition on many occasions. On the other hand, artificial intelligence simply fulfills what is was designed to do. For example, it may even be designed to make irrational decisions, but these poor choices are still by design.