You are a B2B and email marketing expert. Write a detailed, 2300-word guide on storytelling. The guide must cover: 1) Why stories work in B2B, 2) Customer success stories and case studies, 3) Founder and company stories, 4) Industry narratives and trends, 5) Structuring a story in email, 6) Emotional triggers in B2B, 7) Examples of B2B storytelling emails, 8) Measuring engagement, 9) A/B testing storytelling, 10) Best practices.