The biggest gap in interview prep comes from people writing good answers and saying them out loud
Most people prepare for interviews by reading their notes silently or typing answers. Speaking them under pressure is a completely different skill because filler words multiply, structure falls apart, and you lose the punchline.
By the fifth time you say the same story out loud, your delivery sounds categorically different. Not because the content changed, but because your delivery caught up.
Practice by talking, not reading!