Problem is Eastwest Loco, these days in the race to the bottom, contract ground handlers have poorly trained, poorly paid, disinterested staff with big turnover, the turnover meaning limited build up of experienced stafg!
One port i know of has seen 2 Jetstar flights incorrectly loaded, due to inexperienced poorly trained ramp staff!
The Jetstar checkin and load control systems are designed with one thing in mind only..... To be as cheap to own and operate as possible!
Also as mentioned by a previous poster, how can the headcount be out by 16!
Self checkin means the airlines really have no idea who or what state their passengers are in who board their flights!