Best idea is to give him what he wants and hope he doesn't shoot.
First... Hope is not
Second, what if "what he wants" is my life?
I may get no warning or too little to make a difference.
Most just want to get their loot and get out of their without any problems or anyone causing any problems.
I tend to agree, but how does one tell whether the subject robbing you is going to just walk away or shoot you? By the nature of his act -- threatening to do serious violence to your body with a gun, knife, beer bottle, etc., he has indicated his willingness to put your life in jeopardy. There is no way to really tell if a thug has decided you are beneath contempt and he can kill you for sport.
I recall one of those on-line videos of a liquor store hold-up where the perp got his money, then a couple of cartons of cigarettes, gathered up his loot and suddenly shot the clerk several times before calmly walking out the door. Cold
Trying to out-draw someone at gun-point is a measure of last resort. But relying on their charity, kindness or mercy is foolhardy, IMO.