Jeff Cooper once described the traditional double action auto as an ingenious solution to a non-existent problem. The problem, he said, that it was meant to address, was that of having to carry a single action auto with an empty chamber (as militaries tended to require). Cooper observed that this is not in fact a problem, if you merely carry it cocked and locked, and train to flip that safety off while presenting it from the holster. But militaries around the world tended not to permit this mode of carry, thus the "solution" of the double action auto, which permits carry in the ready mode at all times, even by military organizations.
For the civilian, who's free to carry a Browning High Power or 1911 cocked and locked, according to Cooper, one could argue that it was a solution to a non-existent problem, unless you considered the necessity of flipping off a safety before firing to be a problem.
