I don't really rage quit, I just get frustrated when I constantly lose, especially if my team happens to blame me. It tilts me, and I get frustrated, so I just play the rest of the game out and then get off. Mainly happens in MOBAs, like League of Legends, and at the end of the game, I just report the person who frustrated me (and was likely rude to me and/or my teammates, hence causing my frustration) and get off the game until that frustration has gone away. I mainly keep my toxic comments to myself because the people don't deserve to hear those, and it could just be a bad game and I'd rather be helpful and encouraging than toxic.
Losses happen though; they're a natural part of games. Sometimes you just gotta walk away and take a breather and come back to it rather than letting the frustration get worse.