Regarding multiplayer/competitive games like what's been mentioned and referred to:
If there is a game with an online ranking and a competitive ladder to climb, i get in there once I've gotten used to all the basics. I play games because they are fun, but I like it more when i actually win and outplay opponents as i show off what I've learned and what i still need to learn. I often tell people that a competitive mindset is what will help players make progress with going up the ladder, and in order to improve, a player must never be arrogant about their level of play. Always think that there are players who are and will become better than you. And there are players who play for the same sakes - to dominate and show off their talent. These are the players who i want to play against, because if there idea of fun is purely the image of outplaying opponents, then I have to go through them and give them a taste of their own medicine.
The term "playing for fun only" is an illusion by some players in order to hide poor play and the unwillingness to improve and strive harder in a highly competitive gaming environment. Which is why sadly in many online multiplayer games, there will always be cases of being que'd up with scrubs, manchildren, and the "its just a game" crowd. These are the kind of players that I have to actually carry the shit out of because of their inability to actually play against people, and often times i argue with them that if they are going to play RANKED but play like shit, then don't even play Ranked at all if you aren't looking for a Rank to climb on. Its a bother for the people who actually want to climb the ladder and improve, all while having fun doing it.
And yes, I highly respect people who actually have that mindset when they play competitively in the Ranked setting. Whether it be League, Competitive Pokemon battling (Rated OU format), and the like. If one is going to play Ranked to climb the ladder, then you have to play at your best, improve on mechanics, improve on game knowledge, and most importantly, know that losing and winning are the results of one's own mistakes and efforts.
Even in games in League where i lose because of poor/shitty allies, i still see and think about what i could have done better in order to win next time. That's basically it. As a League player, I started to take Ranked seriously at Season 3 and i often got Platinum and Diamond ranks on my main account and smurf account on the on-going seasons because that's basically the same thing that my friends who frequently played more Ranked before Season 3. Know why I won and know why I lost. That's basically it. Widen Champion/Hero pool. Improve mechanics. Read Patch Notes. Practice whats potentially good (Like S5 Jungle Jax) and catch opponents of guard. Make plays, see bitches, and HIT EM WIT ALLEM DAT! Cya nerds.
I also helped a lot of my friends improve because of how competitive and competent i am as a player. I'm a person who hates losing badly. I don't mind losing if i really got outplayed and did my best to still screw with the opponents. But in times that I played with my friends and our team lost because of them playing so poorly (when i mean poorly, they lose lane in 5 minutes) despite my best efforts to carry them, and them not accepting that our loss was because of their mistakes they cannot admit, then i really and clearly get logically pissed not because of the defeat, but because of lame excuses that i hear from people who i trust. I do my best efforts to help them improve so they actually carry themselves and have even more fun. Its fun to win, its even more fun to win as a team. I had numerous arguments with my friends about what it means to play. If they lose lane in 5 minutes without Jungler support, then that's already signs of losing poorly. Can't trade? Can't CS? always getting zoned? Those are things that a lot of people have to consider.
TLDR: I'm a competitive and competent player. My mindset is more on continuous improvement which leads to enjoyment. I don't mind the online gaming communities with the rather unstable crowd. As far as I can tell, I'm often the most quiet person on chat, talking only when i ping out a call or a shot, and telling people "Sorry" if I make a bad misplay rather than argue about the outcome. I'm a person who lives to outplay individuals and show the world what i love to do. I help people improve, even if it means calling them such names such as scrub or shit, and letting them know based on facts and objectivity whey they are playing like shit. I can't say that I'm the best there ever is, since I can't even play Nidalee or land skill shots. But I only play what I'm actually good at, to the point where I know how to deal with Cheese and Counterpicks.
I'd fill this with MOAR TEXT. Another mindset that i think of: Play a certain character. Play it to death. Play it to a level of invincible competence and confidence. By thinking of that, it helps me play my favorite characters or champions without much worry on hard counters or cheese picks. I played Ragna a lot during Blazblue Continuum Shift 1 (best version of Blazblue) and people tell me that Ragna is hard countered by Tager, Litchi, Rachel, and anyone who's anti rush-down (Tager = grapplers love Rush down), Litchi and Rachel = zones really hard, but I don't really worry because I practice often against those matchups. Obviously everyone reading here would know who's my favorite League character. I played him a lot since his release on Season 1 and I've played him against numerous team comps and found what works and what doesn't when picking Xin Zhao against your enemy. Knowing strengths and weaknesses is a must.
Want MOAR? Here's more. Always be prepared for Cheese or Troll picks and Tactics. If i ever have to send out a special wall in order to stop a HAXOROUS (with choice specs and Focus blast), then I have to prepared for it. A lot of people lose against cheese or troll picks because they are unaware of such things working and sticking too much out of the norm. Really good players should be prepared for such. That's where strong game knowledge comes in. Players who rely on Cheese or Troll picks prey on the lack of game knowledge from opponents, fortunately, I read, practice, and experiment a lot in order to punish people who Cheese/Troll. Jungle Nidalee (before it was legit, meta, and OU), Jungle Ezreal? Jungle Twitch? Jungle Lulu? I've read and even played all FOUR out-of-meta picks before, and I know how to deal with them. I relied on my ever expanding game knowledge to prevent me and my team from getting cheesed.