Most shonen anime about some kid battling other people-- the main characters are either already the best, or they show a ton of potential to become the best. Goku is either the strongest man on the planet or he's about to be. Yugi is the best card player in the whole of history.
Ash... Ash learns nothing. He never quite grasps the concept of certain pokemon types being weak against others, captures random pokemon without any strategic forethought, and he enters the gyms in new countries without learning their special battle rules first. If I remember the first season correctly, I think Ash got half of his gym badges as a gesture for helping the gym leaders defeat Team Rocket.