What started the hate for me was the
shit matchmaking for international people (I'm an Aussie). Although they fixed it, it was 5 months over-due and nearly made me quit altogether.
Shotguns ruin this game the most. I mean,
what sniper just snipes and doesn't revery to his shotty? One in two thousand would sound accurate. There range are amazing (no need to make a game too realstic) and also is a cowards way out.
Grendade launchers. In the hands of a n00b, they are really frustrating. In the hands of a pro with [One Man Army Pro], it creates one of the worst experinces ever.
Lastly, the maps. They are terrible. They are many good maps [Afgan, Scrapyard, Terminal] but some are horrendous [Map Pack 1 and 2 and Derail]. The maps are just too big sometimes.
Also the spawn system.
Play demolition and be spawn camped. You'll see