Ikue Otani has voiced Pikachu since 1997. Since Ash's Pikachu can only say variations of "pika" or "pikachu", she was often teased for having what some saw as an easy gig. In in Yomiuri Shimbun (via Twitter user Karubiimunomono), Otani talked about her experiences. "In the beginning, I was often ridiculed with people saying, "It's great that you only have to say 'pika pika'."
"However," Otani continued, "I've never only said 'pika'."
The voice actress explained that in the script, the dialogue only says things like "pika" or "pikachu". Meaning? "If you don't have a clear understanding of what you want to say in the scene and come up with a plan for your performance, you won't convey anything," she added. "Because, if there's the same nuance, then it would just be OK to use [previously] recorded material."
Instead, Otani, who also voices One Piece's Chopper, records new dialogue for Pikachu for each new episode, new movie and new game. Considering that there are fewer tools (read: actual words) for her to work with, no doubt it's challenging to keep the character fresh and expressive.
According to the voice actress, "I give every single word my all."
Top image: PRCM