A bullshit method that's being used in more and more games that are out today. Rather than, gasp, having the bullets go where the crosshair is, game developers somehow think it's better that the bullets follow a completely random pattern around the crosshair instead of INSIDE the crosshair. Since the bullets don't actually go where there supposed to, it means that most firefights you get into mean zero skill, all luck. You might think shooting in small bursts that it would defeat this, but it actually ensues your death much quicker over a sprayer. Moving actually multiplies the deviation tenfold, making it near impossible to squeeze an accurate shot unless you're playing as a sniper.
Games that have random bullet deviation:
1. Battlefield 2
3. Day of Defeat: Source
4. Rainbow Six 3
Guy1> -sneaks up behind an enemy using a Thompson then fires a half a clip into his back-
Guy2> -turns around and sprays his weapon, getting a kill-
Guy1> -places his ironsights right on an enemys head, fires-
Guy2> -snipes Guy1 with an SMG-
Guy1> youve got to be shitting me, I hit him in the fucking head! fucking random bullet deviation ruins everything.