>>51211556There's this old, Japanese only artbook called "Pokedex" that had some early extensive entries. Nidorina's was that it lost the ability to lay eggs upon evolving. piped.kavin.rocks/watch?v=7yy0lzgXAgw&t=15m43s The Gold/Silver dev team might have decided to program that in out of all of the crazy stuff in the pokédex and it's been kept that way for consistency.
