Your question is Explaining the Central Limit Theorem. Take a moment with it on the right.
Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).
You are discussing experiment results with a product manager who is comfortable with metrics but less familiar with statistical theory. They want an intuitive explanation for why sample averages often look normally distributed even when the raw data does not.
Explain the Central Limit Theorem to a product manager.