"Unless you play at a higher level, most Unreal Tournament 3 and Team Fortress 2 games are actually quite casual and rarely require use of a microphone or regular communication – unless you suspect there’s a spy in your midst.
Frontlines, like Quake Wars, isn’t built like that. Instead, it’s constructed so that players need to communicate if they want to accomplish complex goals. It’s something to which the level design is a heavily contributing factor as, in Frontlines, there is rarely any set path or route to follow. It’s an open world – players are given helicopters and tanks and told to do something however they want."