Masashi Kishimoto's Naruto series is considered to be one of the best shonen manga series of all time, having enjoyed quite an incredible run up to 2014. Naruto focuses on the story of Naruto Uzumaki, a young boy in a village called Konoha who aims to become the greatest ninja, called the Hokage, and earn everyone's acknowledgment. Through Naruto, Kishimoto managed to show the fans some incredible character writing and it is safe to say that the protagonist of the story is arguably his very best.
At the same time, Naruto also has a very rich cast, filled with some wonderful characters who all have their own dreams and motivations. As seen in the first part of the story, every character to be introduced received special care from Kishimoto and fans could connect with them on a special level, which was nothing short of incredible. Expectedly, this built expectations for the characters going forward in the story, however, with Naruto Shippuden, the side characters started to become less relevant and didn't receive as much attention from the author. This has been one of the most glaring weaknesses of the Naruto series as a whole and there's certainly a reason behind it.
What Happened To Kishimoto's Side Characters?
As Kishimoto's story moved forward, the series started to focus more on the main characters, and very little time was given to the side characters. For Kishimoto, focusing on Naruto Uzumaki and Sasuke Uchiha was much more important than giving the likes of Rock Lee or Tenten, or even Sakura to some extent, attention. Looking at how Naruto Shippuden dealt with the stories of Naruto and Sasuke, it is quite clear that the two paralleled each other throughout its run and eventually, fought each other. While Naruto was often compared to the light, Sasuke was compared to darkness and this theme became a growing focus of the story with time.
Through Sasuke, the Uchiha clan also received a lot of exposition as the likes of Obito Uchiha and even Madara Uchiha stepped into the fold. The Uchiha generally became central to the plot, being linked directly to the Project Tsuki no Me. On the flipside, Naruto Uzumaki and his Senju relatives became the opposing force for the Uchiha, which is what the majority of the story was all about towards the end.
Naruto Shippuden did kick-start brilliantly with the likes of Sakura Haruno receiving great character moments, such as when she fought Sasori, the likes of Team Guy getting in on the action during the Kazekage Rescue Mission, or even Shikamaru and his team fighting Kakuzu and Hidan, however, that importance did dwindle with time and, the same time was dedicated to showing the fans more about Naruto and Sasuke's growth, and the fate of the Uchiha and the Senju that tied the two together.
Why Did Kishimoto Forget His Side Characters?
To be precise, Kishimoto didn't forget his side characters. Instead, he chose to focus on other aspects of the story which clearly felt more important to him. Kishimoto himself mentioned on occasions that Naruto and Sasuke are the two most important characters in his story and are like Yin and Yang. When one progresses, so must the other. Having two main characters who hold such importance meant that Kishimoto had to prioritize them over everyone else.
This had a profound effect on the story in both good and bad ways, of course. On the one hand, Kishimoto's focus on Naruto and Sasuke gave the fans some of the most incredible characters in those two. It goes without saying that both Naruto and Sasuke are incredibly well written and stand out as two of the most amazing characters written by him. Naruto, with the guts to never give up and the epitome of hardwork, is an inspiration to millions of people across the world. Meanwhile, in Sasuke, Kishimoto wrote what is probably one of the best redemption arcs ever. On the other hand, the cast of Naruto, as a whole suffered quite a lot. A strong series has a strong cast, a rich and diverse world where everyone is their own character and not just there to make the main characters look better all the time. This is, essentially, what separates the greats from the average stories. Kishimoto's characters eventually started to lose their importance and all the purpose that they served was for Naruto to jump in and save the day or for expository purposes during tense situations where they'd just sit back and do nothing.
For instance, Hinata during the Pain arc did absolutely nothing to defend the village but instead, she was used as means for Naruto to transform into the Six Tails state. Tenten wanted to be a Kunoichi like Tsunade Senju yet the two barely ever made contact in the entire story. Neji, a character with an incredibly important story and themes surrounding him, died for the sake of bringing Naruto and Hinata closer. Rock Lee, a genius of hardwork barely did anything in Naruto Shippuden other than throwing Minato's kunai towards Madara to help Guy in the Fourth Great Ninja War.
It is safe to say that not everyone has the main characters as their favorites and seeing them not receive the attention they deserve certainly isn't fun. Naruto, as a whole, suffered quite a lot due to side characters not receiving the attention they deserved and fulfilling the story arcs that Kishimoto set up. That's not to say that Naruto isn't a great series. Kishimoto's work will always be considered to be one of the best stories out there, however, just like most stories out there, it has its glaring weaknesses.