Board Game Arena

If so, how do you explain sometimes the winner get less than 15 points (and there has not concede the game) - sometimes you win and just get 6, 7 points. and obviously if you play with someone with far less points than you (example 300 vs 150) , the points you get are less than if you play with some...

Hello!

Can someone explain the rules behind the points attribution in arena mode? Sometimes when we win we get 15 points, another 8, etc. And the same happen when we lose. I can't see the pattern. Could someone explain me?
Thank you