first of all, wrong category xbox3sh*tty fanboy!!!
they probably mean people who cheat online will get caught. you can cheat online by glitching (look it up if you don't know but if you don't know alreay, you are a serious n00b...)
you can also cheat by using a LAG SWITCH. (my favorite for online). its when you make a control connected to your ethernet cable which when pressed makes that other players in the match lag so you can easily escape danger of being killed. i've made one and it workss like a charm.
ther is something else called a turbo controller. you can buy trubo controllers from shops or you can mod you're own. it's when you press the fire button and you player fires the gun at a blitzing speed. even a pistol will go off like a machine gun. fun to watch and listen to peoples' reactions online but you can be caught out and reported. easy kills come at a price...
it's best to just glitch and cheat in campaign but online it's a complete no no... have fun playing