I'm going to tell you something that I can't easily explain: When I advance the quest, I'm having fun. I barely know why, in the same way that it's difficult to explain why paying off a mortgage in Animal Crossing is fun.
Star Wars Battlefront 2 is made up of many different parts that are pretty good, but the whole is consistently undermined by poor choices in the game's multiplayer economy. No aspect of Battlefront 2 is beyond redemption, but it's hard to fall in love with any part of it, either. It's mostly a disjointed, sporadically fun collection of modes set in familiar Star Wars scenes. Because players have no idea what is really being sold to them, or when, you have a big-name launch that gets in the way of itself more than it creates fun.