That whole network stack was based on a simple premise from the telco world ... that you should charge by the byte for a virtual end-to-end connection (just like we used to charge for a phone call - N bytes and M bytes/min).

IP sort of busted that whole idea - the idea that you could (should!) just drop packets when things get tough ran against this whole idea - but it made TCP/IP easier to implement, and perform better, and most importantly move faster and be adopted as the standard we use today