I see a lot of talk about metrics of skill in BF, whether that be K/D, score per minute, or whatever. Some people say K/D doesn't matter, some say it does. But I think a lot of the discussion is completely missing the point of what is actually the most important metric of skill in BF: impact.
Impact is not measured solely in kills or captures or revives or vehicle destroys, but all of them at once and also none of them. Push an objective and frag out until you and your team cap? That's a high impact play. Load a dirt bike with C4 and ram it into an AA tank that has been pinning your helis down? Congrats, you just earned air superiority. Post up between objectives and lay down fire with an LMG to prevent a push toward your objective? That is way more impactful than sitting on the objective itself until you are swarmed by enemies. Even sniping can be impactful; if you are able to pick off a couple enemies capping an objective and force them into cover, giving your team valuable time to spawn and clear them out, you were a key part of preventing the cap.
But knowing WHERE and HOW to make an impact is the core knowledge and skill that separates good players from useless ones. Situational awareness is the name of the game, not just of what is going on immediately around you but what the state of the map looks like. Where is the front line? Who is covering flanks? What does my team need most right now?
For example: I was playing on Cairo today and my team was doing a great job holding the enemies on A and B, but I opened the map and noticed that nobody was defending the south street from B to E. I switched to Support and set up an LMG down the street, and what do you know: a squad of enemies were trying to flank around to cap E. I mowed them down and ended up staying there the rest of the match, picking off anybody trying to flank. If they had been able to get through and cap E, we could have lost, but I saw the state of the map and knew where best to focus my efforts. I didn't even come close to top fragging, but the kills I WAS getting were much higher impact than if I just threw myself into the fray.
To me, the ability to read the state of the match and make high-impact plays is the single most important skill in any BF. Next time you play, pay close attention to what is going on around you, figure out where you are needed most, and get it done. A single squad or even a single attentive player can be the difference between a W or an L.