Just a couple of reasons:
ELO starts you at the median skill level. This makes it hard for newer players as the get rolled constantly; and what kills you get will be higher ranked players than you, whom are outnumbered or beaten up, and would otherwise flog you. In turn, this buffs your Elo greatly, putting you higher than you are probably ready for.
If you are piloting assaults, well then your time is going to be painful regardless. You are big and nasty, and draw a lot of attention, and require good support to be fully effective. Assaults are great in coordinated groups, or with more experienced players who know how to work well with assaults; but otherwise, you are going to have to really think, be situationally alert, and really be prepared to work your *** off. I have an overall W/L of about .7, but a K/D of 1.17 (which I had to get back from .5, from the early days when I couldn't play for ****); so I do feel your frustration. Also don't stress so much about W/L, just your combat effectiveness.
Finally, ignore folks like Vassago; yes, he is good and knows what is talking about, but it's made him arrogant and insensitive to those not of his skills
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Edited by Mokey Mot, 19 May 2013 - 07:16 PM.