Generate a Welcome Email Sequence for B2B Marketplace

Generate a sequence of 4 welcome emails for a B2B marketplace named [Marketplace Name]. This marketplace connects professional suppliers and buyers in the [Industry Sector]. Recipients are [Target Profile Type] (e.g., executives, marketers, agencies, sales). Each email must be written in English (or as specified) and follow these constraints:

1. Objective: Convert a new registrant into an active user (first purchase or listing an offer).
2. Tone: Professional, direct, without excessive technical jargon, with B2B-appropriate vocabulary (e.g., 'ROI', 'operational efficiency', 'qualified matchmaking').
3. Structure: Each email must have a catchy subject line (max 60 chars), a preheader (max 100 chars), an email body with one key argument per email, a main CTA button, and a secondary text CTA.
4. Specific B2B levers: Mention levers such as reducing acquisition costs, access to a network of verified partners, personalization based on [Need Type], showcasing customer cases (testimonials or industry statistics).
5. Constraints: Emails must avoid unrealistic promises, comply with regulations (GDPR, unsubscribe right), and include B2B-appropriate social proof elements.
6. Variables: Use the following variables in the text: [Recipient First Name], [Company Name], [Offer Type], [Supplier/Buyer Specialty], and [Account Validation Time].
7. Schedule: Email 1: day 0 (welcome + first step), Email 2: day 2 (value added / key features), Email 3: day 7 (social proof / testimonials), Email 4: day 14 (special offer or personalized follow-up).
8. Metrics: For each email, propose an open rate target (e.g., >25%) and click rate target (e.g., >5%), plus a sequence-wide KPI (e.g., user activation rate).

Write the complete sequence in English (or French if specified), with subject, preheader, body, and CTAs for each email.