So here's something I was just thinking. When Ash and his friends first encounter the Tailow flock in You Never Can Tailow (Season 6, Advanced), the Pokédex says that, no matter what, Tailow will never back down from fights, which is shown after Pikachu's multiple Thunderbolt attacks, and even when facing the leader one on one. However, if that's the case, how did Tailow lose so easily against Roselia in that one battle with Drew in Pros and Con Artists (Season 7, Advanced Challenge)?
Well, just because it never backs down doesn't mean that it can't lose. It got hit by a stun spore, and it couldn't fight anymore, it was as simple as that. If it could have kept battling it would have. Drew's Roselia was just stronger
I always thought that's what it meant, though. That's what I interpreted it as from what Brock said, anyway. "Ash, you should put an end to this battle, before you do it any more damage!"
yeah, they've proven many times that in the show, type advantages don't matter in a battle. Helps, but doesn't matter