It’s the only acting that requires you to perform while reading off a script. (Except for TV news and presidential speeches, which isn’t acting. Wait, in the latter example it just might be…)
In theatre and film, reading scripts is called rehearsing. So the challenge in voice acting is staying connected to your fellow performers, which often means freeing yourself from the words on the page. Get your eyes off the page, look at your fellow actor every once in a while, listen to what she has to say. Then respond like the human being you’re portraying. Or maybe just soften your gaze, detach from the print, float on top of it.
If we just read the words then we’re no more interesting than a local news anchor. “Thousands spared today when a lone gunman entered a downtown building and shot his a co-worker.” I honestly heard this on the radio the other day.

