Try and put this simply;
If your ratio is 2.25 for example, if you get a ratio of 2.25 every game, it will NOT go up.
If your ratio is 3 for a game, it will go up an amount inversely proportional to your amount of kills. I.e. if you have more kills already your KDR will go up less.
If you have a KD of 2250 kills and 1000 deaths, that's 2.25 KD but if you wanted to get to 3.0 KD you'd need 750 kills and 0 deaths.

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