I've noticed that sometimes, leaderboard score is applied if my team comes last and I'm the lowest scorer on it, but sometimes it doesn't. Sometimes it only seems to apply if my team comes first, other times it does it if we come second, and sometimes I've had the highest medal score in the BG and it still doesn't actually apply to the leaderboard score.
So, how does it work? At the end of every BG it says "leaderboard score earned" or whatever the specific words are, but that doesn't always actually happen. Anyone know why?