Masque

 

There are many reasons, it ranges from general preference and interpretation to outright lack of information or differences in culture. Some of the smallest are like those who just don't mind or care for Sakura but know her role, others its a bit in between like the rational pairing fans or those who know what Sakura is about and her development yet Hinata or others still take precedence over her to them. Then you get those with the outrageous claims or don't know what they are talking about like for Sakura always hitting Naruto as its said, why is Sakura the one to gather all this attention? Why not the other female anime characters who do the same thing? Others may not know the concept of a tsundere, going from affection to temperamental. Sakura in her case was all kind to Sasuke and all hate to Naruto, but now she is much more caring towards Naruto and much less temperamental but only for the reasons needed like him being an idiot or something. Then you get some of the most outrageous like those who claim Sakura is just some hate filled witch and unsuited for Naruto and Hinata is some perfect goddess. One of the worst cases of insane anti-Sakura views came from RtN in which they got angry Sakura was starring with Naruto in that movie and then AU HInata shows up and yet personifies Sakura they always claimed her to be, and yet they just worshipped this Hinata like the real Hinata should be this. They always spent time hating Sakura and claiming her to be what AU Hinata was and when AU Hinata came around, they said she is some ideal or great match for Naruto unlike Sakura. This was one of the biggest double standards I ever saw and just couldn't stomach the logic these fans used. But fanbase views range immensely, when it comes to Sakura there are minor ones and then you get major ones. Its like some people saw the Sakura-Kushina stuff coming in 631 even if they hated Sakura, others and I mean a lot of people acted like Huh? Is Kishi drunk of something? Is Minato been doing drugs? Sakura like Kushina? No way that can be true its just a joke or a way to mislead people. Or it became something else like WTF Kishi? You are ruining the story! Didn't you just confirm NH as the canon couple! Whats funny in the second statement, the development of NS was nowhere near done yet people thought it was just somehow ended.

Well that's the opinion of mostly NH fans, I don't know many regular readers and watchers of Naruto that believe that Sakura and Naruto won't be ending up together. That being said you can expect that NH fans would decry Sakura as not being heroine worthy since they prefer Hinata in that role but its the non pairing fans who have a dislike of Sakura that is born directly from the pages of the Manga. Whether you want to blame Kishi for "not handling her properly" as I have seen many people do over the years, is of course up to individual opinion. Personally I just look at it as long term character growth, Sakura spent forever in the slump that most main characters encounter at some point and because of that, she has been defined by her lows instead of her highs. Now we are being led to believe that she has finally resolved her feelings and is emerging from beneath the veil of her cloying love for Sasuke. If she doesn't then expect the amount of Anti-Sakura sentiment increase exponentially, conversely if she does break free of it, leaving no doubts that she is over Sasuke (regardless of how she feels for Naruto) expect for the fan base that doesn't care about pairing to rally behind her. Anime fans are fickle, throw in some can do resolve and a new power up and we quickly forget about that time we were mad at a character but that's part of the charm.

Why many fan think sakura failed or not deserved as a main character/ heroine?

Probably because people were tired of seeing her flaws hammered at them so frequently. Its alright that she was meant to be human and able to be related to, but lets be honest how high of an opinion would you have of somebody who keeps pining over huge (arguably evil) jerk. We have a tendency to judge these characters how we would judge real people in the world we live in, you might pity a girl who keeps going back to an abusive relationship with several murder attempts but you would hardly see them as a hero, someone to be admired. That she is the heroine cannot be disputed but the amount of time she was mired in her anguished love for Sasuke left a poor taste with a lot of Naruto audience not just the pairing centric audience.