I'd like to comment something regarding the main reason why some mangas are more successful than others despite having more or bigger flaws:
Characters.
People don't just read or watch something for the complexity or how compelling and well written may be the story. A factor that can get people hooked to a fiction piece is the charisma some characters may have for the reader.
Even if a story is gloriously done, if you don't like or don't really care about the characters then you're not going to like it much overall.
However, a manga with a story with many flaws and deus ex machinas but some very likeable characters, it's going to be much more enjoyable for the reader than the case before mentioned.
Which explains how there're some mangas with dull or repetitive or not-so-consistent stories that are loved by so much more people (Ex: The Big 3, Golgo13, Hajime no Ippo, Detective Conan,etc).
It happened to me this week, when reading Planetes, i came to the conclusion that while it's well written and all, i just couldn't give A SINGLE SHIT about the characters, so i got bored of it and stopped reading.
Same thing happened again while reading Osamu Tezuka's Adolf (And i like many of OT's works, Apollo's Song being my favorite).
Then since i was bored i went and checked on MangaStream (Yes, they're shitty and drop awesome mangas like Vinland Saga, but they're fast) and found latest Bleach chapter (since it's the last to be released each week)...
and shat a brick
Not that Sakura's life being in danger isn't at least a bit interesting, but that twist wasn't nearly as much an impact as Bleach 448's 2 last pages. Holy fucking shit.
That alone created more expectative in me to see what's going to happen next than the couple of volumes i've read of OT's Adolf and pretty much half of Planetes combined. Hell, it's possibly one of the most tension ridden moments since Aizen's pepsiman mode fight.
And of course such expectative isn't due Urahara's plotting shit behind people's backs (like if that was a surprise), but the involvement of Ichigo's dad and possibly Rukia (Both awesome very likable characters) into something that's probably going to crush the protagonist's dream

If it weren't by characters like these, especially Rukia which is my favorite Big 3 character, i wouldn't even bother reading Bleach. And because of them, i'm waiting anxiously the next chapter.
The thing is, character's charisma is something very arbitrary and subjective to the reader's preference, so it's hard to include on a review since it's a hit or miss factor.
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Apollo's Song - Subgenres: Psychological, Angst - 5 STARS
A story about love, madness and hatred.
Chances are you're going to both like it and hate it.
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