So, there's a huge list of reasons why. I will now provide an extremely long list....
Did you know:
- The Anime isn't the same as the games.
What an extraordinary fact! That's right, the anime isn't identical to the games. Here's are some reasons why this is true:
- Pikachu has been with Ash for 5 Generations already, and has gone through many strenuous battles and endeavors. It should be insanely powerful, maybe even a Level 100. Still, Ash fails to defeat the earliest of gym leaders, like Lenora.
- Bulbasaur used Whirlwind!
- Baby Lugia appeared!
So they aren't the same. Things can happen in the anime that don't happen in the games.