Jumping into queue is a commitment. You promise your teammates that you will set aside 30-45 minutes of your life to play a game with them from beginning to end. If you break that commitment for any reason there are consequences. It's your responsibility to ensure that you have all of your affairs in order when you start a game. That is not limited to just personal affairs, but also ensuring that your equipment is not faulty.
You won't be punished for just one leave, things happen sometimes and there's nothing you can do to prevent it. But if it's happening regularly, you should work on getting your affairs in order first before starting a game.