Resource article from Cableorganizer.com explains why a lower number means a larger conductor.
American Wire Gauge (AWG) - a measurement of the thickness of conductive wires - comes into play for the copper conductors in shielded and unshielded twisted-pair cable.
In short, the larger the conductor, the greater its capability. That is why higher-performing twisted-pair cables like Category 6A and some Category 6 products have larger conductors than previous-generation twisted-pair cables did. The issue of conductor size has also come into the conversation when Power over Ethernet (PoE) and PoE Plus is at issue. Questions about heat generation within cables have driven some cabling system designers and users to choose larger-conductor cable when they know the cables will carry PoE or PoE Plus direct current.
But what is AWG? And why are its measurements counterintuitive, whereby a 23-AWG conductor is larger than a 24-AWG conductor? An article on the cableorganizer.com website takes a fundamental look at AWG. The article explains the history of the measurement as well as what the numbers mean. It includes a table that lists the diameter, area, weight and turns of wire (per inch) of conductors with AWG sizes between 0000 and 40. It also answers the question, why does a larger number represent a smaller conductor? Cableorganizer.com explains, "Each gauge is named after the number of sizing dies the wire needs to be drawn through to reach the correct diameter. For example, a 24 gauge wire is drawn through 24 different sizing dies."
