A deck I lose to after 16 turns of shard of sacrifice is boring and uninspired and im going to give it a thumbs down. If its a crazy mutant serendipidy deck that i was neck and neck with until the end until it gets a super lucky mutant which beats me by 1 HP, it gets a thumbs up. The first is boring to lose to, the second is fun to lose to. Thats how i differentiate thumbs up versus thumbs down.