But you can never be sure.... and therein lays the ambiguity. Do you wait until it's too late (error), do you jump the gun (error) or do you rationally look at things, use your tools, and always have one more tool in the works than the one you are using at the moment?
These scenarios are rarely as simple as a guy shoving a gun into your face and saying "give me your wallet". They evolve slowly at times, and we often need to be able to reliably make decisions under conditions of uncertainty. Walking one line while preparing to jump to another is an art form. Being able to go from Yellow to Orange, and then NOT and I mean NOT NOT NOT jumping to Red without really needing to requires discipline. I've seen way too many cases of "Color Code Inertia" happening, where someone jumps straight from White or Yellow to Red without pausing at Orange, without any reason to be in Red. Witness every cop emptying his magazine at some poor guy for pulling out his wallet. Adrenelin and switching to the "Monkey Brain" where winning a "Dominance Display" becomes more important to the narrowing perception of that primitive thought process than simply leaving unharmed is something to be aware of. Don't fall into the trap. The posters who thought that the next step that I might have contemplated if he had entered would be to shoot rather than to bail out of the other side of the van are showing their own Monkey-Brain thought process response, not mine. It's interesting to observe. It's they who need more training, not me.