Dominion has not failed as long as there are people playing it. 30 million people didn't start playing Summoner's Rift right away, it takes time. However, SR is holding dominion's back because many people do not like changes, putting the time they spent in SR to waste and becoming somewhat noobs. Moreover, SR is a widely popular style, so it's popularity will only draw in more players, leaving only few for Dominion. All in all, Dominion can certainly be much more if not for SR. As it is now, the only people who play Dominion are the ones who dislike farming and want fast action. On the other hand, if Ranked game were to be released, then there will definitely be groups of individual who will compete for the top ranking. When that time come people will pour in to play Dominion, because as far as human nature concerns, not everyone likes SR style, and even if they do, they must get bored of it at some point.