Do you have an idea on how the MatchMaking (MMR™) System work? i'll give you a basic insight; as you may know everyone starts with the same mmr which is set to 1500, so let's say you won some matches and got all the way up to 1600 mmr, and while you're in the que, another team with 1700 mmr is in que as well, after some time the system start expanding the range of the mmr, rather than looking for teams with 1650-1750 mmr, it expands to teams with 1600-1800 mmr, and that includes your team and bingo! Que pop.