So in the games when you get a badge it'll show that the Pokémon can listen to you up to a certain level, this is obviously a game mechanic and some people will simply brush it off as that. But I'm curious as to why Pokémon want their trainers to have a certain amount of badges, when something man made like that shouldn't really be all that much of a concern to them.

So my question to you all is, what do you personally think the reason for this is? (let's disregard that it's a game mechanic for the sake of this question and thread)