Why alliance side can't won BGs?

[haemorrhage2]

Title,

WHY?

[Killroi]

Horde has a higher average total honor per character, possibly due to multibox carries or trading in stone keeper's shards for honor (for low tier, but still, pvp gear) whereas Alliance teams that are all 1 man pugs usually half half or more of the team with 0 resilience.
Add that to poor teamwork / team comps and you'll find an answer.