Ash's victory over Cynthia in the World Coronation Series marked a significant milestone in his character development. Unlike Leon, who was merely a rival that Ash wanted to defeat because no one else had, Cynthia played a more mentor-like role in Ash's journey. She first appeared in Diamond and Pearl, helping Ash confront Team Galactic and encouraging his growth as a trainer. In Black & White, Cynthia continued to guide Ash and even his rival Iris. Ash defeating Cynthia in the World Coronation Series was a culmination of a goal he had been working towards for over 600 episodes, showcasing his growth over time. This victory against his long-time mentor was a better indicator of Ash's growth than defeating Leon, as Cynthia had a much deeper influence on him. The battle with Cynthia truly highlighted how far Ash had come since their first meeting in Sinnoh.