The Arena Matchmaking is Broken, It arrange sthe players into crews as they enter the lobby.
The wait times are ridiculous. The arena matchmaking has a flaw. It creates the crews as players join the lobby. Inevitably, a player ; gets tired of waiting, disconnects, has a wife, has kids, has life. And leaves.
This results in a crew that's a man down. This usually happens multiple times resulting in multiple short handed crews. The game won't start till they are full.
This will sort of be less an issue during prime hours. More players in the pool. However, this will still be an issue late night, month from now and so on.
The lobby should be focusing on getting players in first and starting a timer once a certain number is hit, locking the lobby and. Arranging the crews to start at this point.
That's why you've been in lobbies with 16 people but the game won't start, there's a possibility of 4 crews with 3 players and one full crew, equalling 5 crews in the lobby.
If there are 12 people in a lobby, it should then make 3 crews and start.... But the way its set up, it could be 3, 4 or 5 crews all with a missing player.
Hope that made sense.