Honestly the biggest problem I have seen in any match lost is lack of teamwork.
This is especially true for Huttball where I often see the other side move as a coordinated group accross the field of play instead of just wandering around killing aimlessly. Folks need to come to grips with the fact Warzones take strategy and it is not about top kills here.
Huttball is about scoring, Void Star is about getting through the doors and Civil War is about controlling 2 points - those of you who keep thinking you can get three are the ones who keep loosing the game more often than not. You will get more objective points by defending and letting them come to you than by running around the field getting waxed by the other side.
Speaking of civil war I personally have sat at the left control point alone the entire game (which we lost) while the entire rest of the team failed to take either of the other two points because the ran around the field killing aimlessly. I ended up with 4 medals after doing 0 protection, 0 dmg and 0 healing, why? Because I got the most objective points on the whole team.
If the rest of team had worked together and taken one other point and then defended that would have been 8 medals when the other side tried to take the point back.
Point is work together and your medals, valor and everything that goes with it will come rolling in.