For an anime series to be 'great,' it's supposed to fulfill various criteria. The most important criteria it must first fulfill is to be watchable. In order for a show to be watchable, it must avoid being annoying/stupid, and it must avoid being boring. Most shows don't survive this initial cut. But for a show to be truly great, just being able to watch it all the way through without getting disgusted with it, or tired of it, and quitting, isn't enough. You should really be able to watch it two times through, and enjoy it just as much in hindsight as you did the first time. The show should be deep enough and strong enough to keep your attention the second time through, allowing you new insights and new pleasures you missed the first time because there's just so much good material in the story to be mined.
Of course, for the truly great shows, you should be able to watch them any number of times through, five, ten, or a hundred, and you'd never get bored with them no matter how many opportunities you had to see them. But that hurdle is asking a little too much, so two is a fair compromise.
However, it's somewhat senseless to watch the same show twice in the same year, because one's memory of the show is still so fresh that nothing new could be added to the experience by watching it again. Letting the show settle into your long term memory and separating a distance from it emotionally before picking it up again is vital to gaining any new insights into the show you missed the first time. Therefore, a show can be great even if you haven't watched it twice, if the first time you watched it was only a year or two ago.
The other exception to this rule is if the series is an enormous franchise with many parts. Sequels, prequels, multiple arcs, spinoffs, etc. In that case, it sometimes happens to be true that portions of the franchise are excellent and easily watchable twice, whereas other portions are awful and difficult to impossible to watch even the first time. A show like this gets a pass so long as you truly do love the 'excellent' portion and watch it twice like a good show should be watched. Ghost in the Shell, Macross, Pretty Cure, Tales of 'X', even the Fate series falls into this type of category, with many different parts all largely disconnected from each other, only loosely one series to begin with. It's easy for some portions to be great while others aren't.
The final exception to this rule is if there's some technical barrier interfering with the ability to rewatch a show, like the blu-ray subbed version not coming out no matter how long you wait for it. Generally this problem overlaps with the problem of having seen the show too recently, but sometimes fansubbers drop the ball and the time it takes for them to sub a product extends even beyond that two year window. This is true of cases like Valvrave, Hayate Cuties and Chihayafuru. No doubt it will be true of many more shows, as it somehow feels like fansubbers are falling further and further behind these days. Well, they're working for free, so we can't expect too much from them in the first place. This unfortunate trend is to be expected in our fallen world.
With those exceptions in mind, is there any show I've listed as 'great' but haven't watched at least twice without any excuses left?
The answer is no. Out of the 170 series I've listed as great, I have watched and rewatched every single one of them that a) has a bluray release/is an older series and therefore only has a dvd release, b) is the actual good portion of the show, and/or c) came out more than two years ago. It takes years of effort to watch this much anime, so being able to claim that you've even rewatched it all is an even higher level of devotion. It's something not many people can say about anything. As a result, my rankings are more supported and beloved than any other fan's halfhearted attempts at any other ranking. Unless they've accomplished the same feat as I have, and watched and rewatched every single series they claim to like, I'm afraid they just don't have the judicial standing to truly debate quality with the likes of me, the one true fan of good anime in this world. (And just wait until my rankings reach 180, becoming even more exhaustive and expansive than they are today!)
I've even gone beyond that. Many of the shows I no longer have in my rankings, like Ninja Scroll, Akira, Noucome, The Girl Who Leapt Through Time, Howl's Moving Castle, etc, I've also watched and rewatched. But after careful judgment, after reviewing how I felt the second time through, I decided the show wasn't as rewarding as I remembered and threw it out. Even though the show was watchable twice, it just wasn't quite great enough to merit recognition to the outside world. Unless it leaves you with that glowy, warm feeling the second time through just the same as the first time, it shouldn't stay in the rankings. It has to leave a good impression both times, not just somehow struggle through both times, limping to the finish line.
In order to keep this stellar record, I'm going to have to watch a lot of shows again this coming year (so that it doesn't fall out of that two year grace period for a show recently seen the first time). But out of a determination to prove my belief and faith in these shows, I promise, as a New Year's resolution, to definitely do so. Sometime during 2015, I promise to rewatch all the shows I haven't rewatched yet that are technically possible to rewatch and are the excellent/pivotal portions of their respective franchises:
Binbou Shimai Monogatari
Tamayura: More Agressive
Even though these shows seem old, except for Tamayura, I only recently just discovered them by diligently searching backwards in time for good series I may have missed in the past. Tamayura: More Aggressive starting coming out in July of 2013 and only finished coming out in June 2014 so I've still got at least six months of spare time to rewatch it without violating any rules.
My 'Lost World' anime hunt occurred in the autumn of 2013, so I've got at least nine months to spare in their cases.
As for Valvrave, Soul Eater Not, Chihayafuru, Wake Up, Girls!, Atelier Escha & Logy, etc, there's nothing I can do until the blu-ray subs come out, however long that takes. The rewatching is supposed to be the final, complete watching experience. If it's imperfect, because the best version of the release isn't out yet, it isn't worth reviewing. The true, perfect, final version is not yet available, so there's no point in rewatching it yet. The experience won't be any different from the first time!
Hunter x Hunter only just finished in 2014, so I still have a ton of spare time before I have to worry about it, even though I have no interest in a blu-ray version of this story, since like most long franchises it never specialized in visual grandeur to begin with.
Currently I'm sitting pretty on clearing my own benchmarks. Not only have I watched in full every series in my rankings, I've also rewatched in full all of them, barring the three exceptions to the rule I've reasonably set up that no one could possibly quibble with. So long as I rewatch these eight series within the year, I will have continued to protect this promise and guarantee of 'greatness' inherent in putting them into my rankings.
To put it another way:
Terrible = Couldn't even watch 1 episode.
Bad = Couldn't watch 3 episodes.
Mediocre = could watch at least 3 episodes.
Good = could watch the entire series in full.
Great = could rewatch the entire series in full.
The 170 'great' series I have listed in my anime rankings have all reached that final level of quality. They're also among the top 1/3 of those shows that have at least reached the 'mediocre' barrier. (In fact, by that standard, I could actually extend my rankings to the top 178 currently, but have refrained due to a lack of good material worth recognizing.) They're also shows I not only managed to rewatch, but actively enjoyed rewatching, leaving a good after-impression on me both times. They also accomplished many other feats, like being unique, memorable, emotionally moving, deep, having lovable characters, inspiring, etc, etc, etc. Basically, I can't say enough good things about all 170 of them. They've all earned my love, and should be shown to and loved by the whole rest of the world as well. People could learn a lot from these 170 shows. A lot more than they ever learn in school or church. That much, at least, is certain. There's no excuse for not liking these shows. Anyone who doesn't is either stupid or evil. They must be reeducated. Until they 'get' why these shows are good, they'll just have to keep being shown them over and over in the concentration camps with their eyes held open like in Clockwork Orange. Sooner or later the innate greatness of these works of art will pierce even the thickest of skulls, and all will bow down and worship their new gods. And I am the 170 new God's Prophet, the Final Word on Anime. ^_^.