22) The Brother Theory

BUSTED, the anime and the manga are two separate canons


Why is Satoshi/Ash so inept compared to Red?

It is a gross misconception that they are intended to be the same character in different incarnations. In fact, Red and Ash are brothers. Red is older by a couple of years - so he started his Pokemon journey around the time of the game’s release, and Ash is the younger brother who started his journey around the time of the Anime’s release.
Where Red took down all of Team Rocket, the most influential crime syndicate in his country, Ash has a constant rivalry with two completely inept members of the organization that don't apparently take any part in the real endeavors of Team Rocket.

Red is a Pokemon Master. He defeated the Elite Four, even uncovering a lot of their double standards as Team Rocket members.
Ash has not defeated one league yet.

The reason for Ash’s incompetence is that he has some learning difficulties/mental retardation. However, he looks up to Red completely and is living his life trying to be just like his big brother and idol.

This is why Gary/Green has no interest in Ash whatsoever. He had his fight with Red, and now occasionally meets Ash along his journey, essentially to check up on him.
This is why Brock and Misty, two Gym Leaders, who have an important job to do in their own towns abandoned their posts to travel with Ash. Red had told them about his brother, and they recognized him, and traveled with him to look out for him and keep him relatively out of trouble when Red couldn’t.

Once Red became a Pokemon Master, he went missing. It wasn’t until three years later that he was found up Mt. Silver.
After Red's defeat on Mt. Silver, he sent Pikachu back to Pallet Town to be with Ash. Pikachu didn’t like it, but knew Red was concerned about his brother.
That’s why Pikachu is so wildly overpowered, despite having no obvious training from Ash. Pikachu of course becomes attached to his new ‘trainer’ and wants to protect him.

Essentially, Red paved the whole way for his simple minded brother, becoming a champion along the way. Most, if not all, the other characters that knew both brothers were playing their part to take care of Ash.