Personally I try to stick out my online fighting and it may or may not pay off.
I understand the single player games that are hard that'll make you want to boot your console (Uncharted 3) What I don't understand is why would you want to quit after two rounds? You should have left during the first round if you didn't like it, don't waste my time by playing two holy matches then quitting THEN complaining.
Rage quitting isn't the same as quitting AND complaining.
If I get bodied by a Cyrax, and I just leave after that match in saltiness, but don't send any hatemail, that's acceptable. I lost, and he got a win.
Quitting mid-game, or quitting during finish him, or quitting and complaining is a whole different world.
I rage quit in RE6 all the time because I think so highly of myself, so if I die:
1.) I feel useless
2.) I feel like I wasted both my time and my partner's
3.) I feel embarassed
4.) I don't want it to happen again
So I quit to the main menu, and I carry extra anger if I died because of some bullshit.
Raging at a game isn't healthy, so if you can't get it right after the first few times, and you're boiling with anger and frustration, quit.
Because anyway, let's say Yung beats me 14 times in a row in MK, then I beat him, then I quit, feeling satisfied. I'm still labeled as a wuss because I quit, but I wanted to finish, feeling good.
So I won't give up right away, but if there's like less than a 30% chance of me finally getting done what I want done, screw that. I have better things to do, and video games are supposed to make me happy, not make my day worse.