ash&charizardfan
Humans are tools
I don't really agree with Aipom being an empty slot. During her tenure as Ash's pokémon, she's had some decent battles, screentime and development. It only become toxic waste after the whole trade thing.
I think it had to do with the trade thing and the later parts where aipom just went which was stupid, this makes aipom's worth in ash's team as waste ash just could have caught buizel straight away and dawn would have caught aipm in DP instead of ash catching it towards the end of AG and wasting a non hoenn pokemon spot in his team with an actual hoenn pokemon.