Through my own experience I know I have gone through the following 5 stages of learning this game. I have also been able to recognize these stages in others.
Stage 1 - You haven't got a clue. You still think Spitfires are OP because they do everything well but nothing great.
Stage 2 - You have learned to kill stuff but not how to win. At this point you know how to boom and zoom, you understand ACM, you have developed good situational awareness, and you can put up good scores in almost any plane but you still don't understand why you still lose battles. You might even have a decent win rate by this point but most people still use the excuse they play for fun but not to win as if the two are mutually exclusive.
Stage 3 - You have learned to win. You know how to work the maps and know the bot behavior and patterns. Even when you do lose you know why and what you did wrong. You take responsibility for your own actions and don't blame bots or RNG for everything. You start looking at your daily win rate but its more out of curiosity than a major motivating factor.
Stage 4 - You start to get overconfident and experiment with maximizing points and medals while still trying to win. You end up losing more battles because of your own ego than anything else. You try to drag out battles too long and it ends up costing you the win. The upside is when you aren't screwing around you can carry most battles.
Stage 5 - You know when you can screw around to maximize points and when not to. You know your own limits and win consistently. This is the stage winning becomes important to you.
I'm sure there is probably a stage 6 or even more but I'm not there yet. I know I am still learning and trying to improve so there must be more.