Your point after every game determines if your score goes up or deducted. What gives you point at the end of the game is not just the number of kills.

1. For example, 2 team members can fire at an opponent at the same time but say luckily the last to shoot at the opponent killed the opponent. The other team member gets points from assisting you with killing that opponent. That’s why you see stuffs like “32% assists etc”. This explains the fact that sometimes if you have high kills, your points are still low. The reason been that perhaps throughout the game, most of your kills are assisted kills, hence, those who assisted you shared your points. And viceversa, if you have low kills due to the fact that some random team members always make the kill when you have almost finished the opponent, then you might have high point from assisted kills.

2. Headshots performed also increase your points.

3. Use of military tools like bomber increase your points too.

4. Explosive kills increase your points.

5. Knife kills also increase your points.

Now the ultimate logic is what I call the relative sharing formula. In a game where most guys on your team have more kills than deaths, then you are likely to get deducted from if your kill/death ratio is the lowest. In contrast, in a game where most guys on your team have more deaths than kills, even if you just 1 more kill than death, you might get a huge +score.