Voiceover and sound design for whiteboard animation
In a strong whiteboard animation, sound is not a finishing layer. Narration establishes the pace, drawing directs attention within that pace, and music or effects support the emotional contour without obscuring the message.
That is why recording a voiceover after every visual has been timed often creates unnecessary rework. If speech is the main carrier of information, it should usually become the timing reference before detailed animation begins.