Masashi Kishimoto was forced to work on the Chunin Exams arc in Naruto.
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The Chunin Exams arc in Masashi Kishimoto's Naruto is one of the most prominent arcs in the history of the series. And the main reason for this was the introduction of several characters from all walks of life, who compete against each other to become Shinobi and earn respect for themselves in the world.
While themes of competitive fighting were quite common in anime and manga series at the time, Kishimoto managed to put his own twist on Naruto's Chunin Exams by introducing different jutsus. It certainly helped the series in a big way, but unfortunately it wasn't Kishimoto's idea. It was actually Kishimoto's editor who came up with the idea of the Chunin Exam.
Kishimoto once revealed that he never intended to introduce competitive battle arcs in his magnum opus, as they were very difficult and would take the mystery out of the story. However, his editor forced him to work on the Chunin Exams, which became a great boon to the series.
