This episode was okay. I can't believe Pikachu lost to that water monkey PKMN like an amateur. And for all those who keep saying "IT'S ONLY BEEN 5 EPISODES, PEOPLE. DEAL IT!!", you're wrong. It's been over 600 episodes and we're still seeing Pikachu getting pwned by an amateur. That's what's ticking people off.
Maybe people should stop and think what actually happened. If you saw the episode you should know why Pikachu lost the way it did.
First off, Ash hasn't even been a trainer for a year(1st episode of BW, it said he was 10). Gym Leaders most likely have years of experience and Koon could pass for 15 or so. Assuming if he started his journey at 10 then that's 5 years of battle experience for him, 5 years is more then less then 1 year.
Second off, Gym leaders are strong and aren't push overs. You wont beat them easily for the most part. Koon and his Hiyappu aren't amateurs, neither is Ash or Pikachu, and they aren't being show as amateurs either.
Now for what actually happened in the battle, Ash didn't forget Pikachu could use Electric moves(Like some people joked about before even watching the episode) he even declared Pikachu to use both Thunderbolt and Volt Tackle, but Koon reacted quickly to both and had Hiyappu use Water Gun to cancel out Thunderbolt and Mud Sport to cancel out Volt Tackle. Not to mention Hiyappu seems pretty good using Double Team which messed Ash and Pikachu up. I don't think Pikachu was even able to get a hit, that just goes to show how strong Koon is.
Just because Pikachu defeated a Latios and a Regice doesn't mean it's invincible and can't fall in battle. Battles have a lot of different factors in them, skill, luck, and the mood of the battlers. Ash was just unlucky that Koon was skilled and had ways of dealing with Electric moves.
Also, just because a Pokemon has a type advantage doesn't mean it will do great, since it's already been shown that type advantage doesn't automatically equal a win.
So the battle was fine, Pikachu lost so what? It lost to someone who know what he was doing and was prepared for anything.