Penalty

I was reading rules(Groups & Teams Help Center-how leaderboard points are calculated):

   There should be some penalty to those teams/groups that quit team match against other team/group....

   If you agreed to a match and you withdraw from him because you think your team will loose your team should get some penalty! It is not fair to waste time and start only matches that your group will win....

  What should penalty be?(when canceling match that was open for registration more than 24 hours.This way when match is open for registration but there was mistake in settings there will be no penalty)

Maybe:

-loosing leaderboard points: 100?500?

-when team cancels 5 team matches he loses 1000 leaderboard points

-some other?