I'm not sure where else to put this, but this seems to be the most active card game thread atm.
To some relatively good success, I've applied arbitrary goals to other games that have an undefined ending. For example, instead of playing PoE until I get bored, I stop playing when I reach a certain amount of challenges. I said relatively good success. I still play too much until I reach that goal, but afterwards, I pretty much stop. Talking with my brother, he had a similar problem with Hearthstone. Instead of addressing the issue(maybe that's not possible?), he's pretty much done with CCGs.
I was wondering if anyone else has had success with applying this to a CCG. This does sound similar to people that say "I get to rank X and then stop", but that sounds more like they don't want to deal with the assholes and grind above X than considering X their true goal.