>>29174450>Not realizing how long it takes to design PokemonNWR: On average how many Pokémon designs get thrown out over the development of the game? Have any rejected designs come back in subsequent generations and if so, which ones?
Hironobu Yoshida (HY): With each game we are always working with a different theme with the Pokémon for the generation. And the designers themselves, depending on the time, they’ll have different things they’re passionate about and different things they want to try. Although we come up with ten times the amount of ideas for Pokémon that make it into a game, even the ones that get rejected don’t typically come back in future games because we’re trying new things and match the theme of the new game. The things we’re passionate about are different than they were in the past. Also, in terms of the design process, even once an idea is selected, even from that point the design changes quite a bit since it takes about six months to a year to finalize a Pokémon design.
http://www.nintendoworldreport.com/interview/35513/pokemon-x-and-y-interview-with-game-freak 
