What do misses mean to you? Not active dodges, but attack roll misses?

In games with just one roll this has always been easy to interpret for me: for instance, in d&d, when you roll to attack you are rolling to land a solid blow on your enemy, and this chance is automatically modified by your opponents armour class, which includes things like his armor and dodging ability. "Missing" in this case simply means your blow wasn't effective, either because it was dodged, because it bounced off armour / a shield, etc.

In GURPS however, I'm not really sure how to see it. It obviously can't always be a miss, you'd have to be superbly incompetent to thrust wide of your opps torso in melee combat for instance. In cannot represent a swing to the shield or armor bounces either, because those are accounted for in active defenses. It can't mean that "the opportunity to strike simply didn't present itself, so technically there was no strike attempt in the first place", because weapons go unready even after failed attacks. What the fuck is the correct interpretation then?