Here's why:




The PLD in the screenshot did about 5k more then the average DPS there, yet he gets 10 kills? That basically means he ran around and stole kills, because there's no way a PLD can blow up that many people by spamming RoH, especially in a 8v8v8.

Because it can take so long to kill someone, especially a skilled healer, kills being based only on getting the final hit drains all the value out of the scoreboard. I always take killcounts with a grain of salt, and you should too.