What primary goal is achieved by using private IPv4 addressing on a network?

Private IPv4 addresses (like 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16) are not routable on the public internet. This means devices using these addresses are inherently protected from direct, unsolicited connections from the internet, as internet routers will drop packets destined for these ranges. This provides an added layer of security. Network Address Translation (NAT) is then used to allow these private devices to access the internet. While NAT can reduce the number of public IP addresses needed, which indirectly affects router table size, the primary goal of private addressing itself is not to reduce table size. Private addresses cannot directly communicate across the internet or public network boundaries; they require NAT for this.