Ash Ketchum in the Pokemon manga is a character that has been appearing for 25 years and during that time he has shown his remarkable growth.
Back in the early days of the Indigo League, Ash’s personality was almost unlike anyone else’s except for a few key traits.
Another arguably more important aspect of Ash’s character is his willingness to sacrifice himself to protect his pokemon.
Ash is quite lazy, using every fastest route he can think of to find his badge.
Luckily for Ash, he has many opportunities to learn.
Ash also started paying more attention to others when he left Kanto.
However, the most important point of growth that Ash has is his standing with his opponents.
Another good example of Ash’s growth is his confrontation with Paul in the Sinnoh region, which solidified Ash’s style and motivation for training Pokemon.
He may only be 10 years old by the end of the series, but he has definitely grown up a lot over the past 25 years of the series and this will continue.