For the same reasons as this: http://bugs.verdungame.com/topics/1352-make-rear-areas-desertion-zones/
...please put in some sort of visual feedback for players that spend A LOT of time camping behind their own team's trench instead of getting inside/defending it or inside their own trench while the rest of their team is trying to capture the enemy's.
60 seconds or more? Total in 1 phase, not 60 seconds continously spent in the same area, otherwise you'll have people leaving that area after 59 seconds to avoid the message and returning 2 seconds later...
You could make the screen flash messages like "Move forward to capture the enemy trench!" / "The enemy is capturing your trench! Defend it!" in bright red, with the same placement as the "You're blinded" or "Press 3 to use iron sights" messages (but slightly bigger). And/or automatically play soundbytes to help reinforce the message.
It would give more direction for newer players ("where do I go?") and less excuses for snipercampers along the lines of "if they didn't want snipercampers, why are there scopes in the game/why can I run back 3 trenches then without getting punished?". If doesn't help much, make the screen slowly go turn dark/gray in addition.
When the game itself is telling players to PLAY THE OBJECTIVE (and how to start doing that) in an aggressive manner, new players have more guidance and the occasional snipercampers might feel pressured enough to actually do that from time to time.
Play a couple of public Frontlines matches and you will see more than enough players either saying "where do I need to go?", "I don't know where to go!" or simply refusing to play the objective at all, instead camping somewhere in a far off corner, being useless to the team and defending themselves with "I'll play however I want, if they didn't want me doing to play lone wolf, why does the game let me?"
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