I'm not one to quit a game because the game is difficult. But there are times in multiplayer matches where I say, "Fuck This!" and run away.
In Modern Warfare 2, I'm more of a CQB player, UMP (Rapid-Fire), USP (Tactical Knife), Marathon Pro, Lightweight Pro, and Commando Pro. (Class Name: Howdy!)
My friend Pat is always a sniper with the perks Barret (Heartbeat/Thermal), Thumper Grenade Launcher, Bling, Cold-Blooded, and Ninja... he is nearly impossible to find and he always guns for me when we run into eachother online.
There was one point where I heard one of his shots whizz past me, and I said, "Fuck This!" and ran for cover instead of trying to kill him.
Ultimately, running away then, let me flank his sniper's next about 30 seconds later. I got so many points off killing him: Headshot, Payback, Rescuer, and Buzzkill.
So remember, a "Fuck This" now can lead to a "Fuck, Yeah!" later.