Just because there have been instances in which pepper spray did not work (for whatever reason), it is illogical to conclude that it is ineffective. Often, guns are applied ineffectively, as well. Here is an example. No one is claiming that pepper spray is a magical paralyzing foam that stops all badness when it is deployed. It needs to hit the eyes for maximum effect or at least the mouth and nose. Firing a gun and missing is just as ineffective as firing pepper spray and missing. The value of pepper spray relates to its portability and, most significantly, to its almost universal legality.