Because it was better than the format two months ago where only two decks were viable.
Actually, that was the best reply to my question you could have possibly come up with, and I agree 100%. At one point here in NC there were 2 viable decks: Kricketune and Mario. Mario was being played so much that I could never get away with a Blissey deck. It wasn't that Blissey couldn't win against Mario, it was just that I was facing Mario matchups 3 out of 4 rounds or so, and as good as Blissey is, it's hard to go against something that can T2 a 130 HP Pokemon.
What's worse is that those decks required absolutely no skill to play. I witnessed it myself. At the first Battle Roads we had I played against a guy playing Magmortar/Infernape. It was his first Pokemon tournament ever, and I had to help him out every step of the way. The next day I played against him in the top 4 -- he was playing Mario. I still had to help him out the whole time. No disrespect to him at all, but it's sad when brand new players are sitting in the top cut because of their deck.
Though I feel that GG requires a reasonably low amount of skill to play (notice I didn't say "play well"), it's still infinitely better to see than Mario or Kricketune.
Man, now that you mention all of those decks, i miss last format so much lol.
See what I mean? And it's not just the decks, it's the strategies as well. Damage spread, disruption, speed, status conditions, stalling, teching, trainer lock, stadium lock, decks that have variable damage output, deck destruction, bench damage, Poke-Power counters, "beatdown" decks...
Now we only see decks succeed if they can accomplish one thing:
The occasional OHKO. I was planning an article on this subject, and I may still go through with it, simply because it is the most important thing for decks to do these days (with the only notable exception being Blissey decks, though even they can grab a couple OHKO's during early game). Hurricane, GG, Magmortar... all of these decks are successful because they have a variable damage component to them. Whether it's an attack that does 20X the amount of energy present or an attack that does 20X the amount of energy shown, whether it's the flipping over of prizes or a late-game Bring Down, this is what makes these decks so viable. The prize swap is always in the favor of the GG/Magmortar/Hurricane player unless the other player is using a strong counter (which is hard to find at the moment).
There is the argument that GG/Magmortar/Hurricane all have different elements of strategy that I've already listed, such as bench damage (Magmortar), teching (GG), or disruption (Hurricane). But these are not the main foundations of these decks. What is Magmortar without Flame Blast and a couple of Scramble Energy? Or GG without Psychic Cut doing up to 180 damage in no time? And we all know where Hurricane would be without its first attack. The single biggest factor that makes everything else nearly unplayable at the moment is the fact that other decks lack this occasional OHKO, a factor that essentially represents one strategy: "Beatdown."
