Platform: Windows, Steam
During a traditional constructed event, when you press cancel during the loading screen while there is the "Entering match..." dialogue, it seems the game will count that as a loss and remove a game from the event (x game remaining counter).
In my case, I played one match, then, for the second match, pressed the cancel button before joining it because I changed my mind.
Later in the day, I played one more match and after that match, the game was showing "2 games remaining" in the event tab. Though my game tracker only shows two matches played in that event.
I excepted it to show "3 games remaining" instead.