Early in the series when Charmander evolves to Charmeleon, almost right away it begins to disobey Ash and refuse to listen to him. this continued to Charizard who would lounge around and blast Ash with a fire breath until he was frozen in ice during Ash's travels though the Orange Islands and Ash stayed up all night trying to melt the ice.
from what i remember Charmander willingly went with Ash when it's trainer abandoned it and he was about to die from the rain. if i followed the game logic i could assume that it was because Charmander's Level went too high in comparison to what badges Ash had however....
- there was no signs of disobedience until after the evolution
- the 8th badge of any region allows full control no matter the level however Charizard was still disobedient even after Ash got Kanto's Earth Badge.
- not to mention that the level control ability of another regions badges would be made obsolete for someone like Ash who gets badges from other areas
So what caused Charmeleon to become so disobedient to Ash?