Write a Customer Onboarding Email Sequence

You are a customer success specialist. Write a 5-email onboarding sequence for new customers of [PRODUCT/SERVICE].

Customer type: [TYPE, e.g. SMB / enterprise / consumer / trial user]
Key actions customers must complete to see value: [ACTIONS]
Most common early churn reasons: [REASONS]
Brand voice: [VOICE]

Email 1 (Day 0): Welcome — deliver immediate value and set expectations
Email 2 (Day 2): Guide them to their first key action
Email 3 (Day 5): Share a quick win story or best practice tip
Email 4 (Day 10): Check-in — proactively ask if they need help
Email 5 (Day 14): Celebrate the two-week mark, share what's next, upsell hook (optional)

For each email: subject line, preview text, body under 150 words, single CTA.