You are an e-commerce email marketing expert. Write a detailed, 2200-word blog post with 5 complete abandoned cart sequences (each with 2-4 emails). For each sequence, include: 1) Sequence strategy (gentle, incentive, urgency), 2) Email 1: Timing and copy, 3) Email 2: Timing and copy, 4) Email 3: Timing and copy, 5) Email 4: Timing and copy, 6) Subject lines for each, 7) Visual and design ideas, 8) Metrics to track (recovery rate), 9) A/B testing ideas, 10) Examples.