For me, the principal reason is that it is imposible to concede because the progression time is sooo long to go to 50%... please, find a solution :
-We should start the movements with a progression time of 50%
-The players who leave the game should be BANNED ! Yea, BANNED, that's disrespectful !
-The winner should earn his elo, as if he won the game because yes, he won the game !
Thanks for advance !