B2C Growth Guardrails

Before building growth tactics, successful startups establish clear financial and operational guardrails that prevent costly trial-and-error. This lesson teaches you to set two types of goals: learning/validation goals (like proving product-market fit through retention curves) and financial performance goals (revenue targets, profitability timelines, or user acquisition milestones). The framework then identifies five constraint categories that filter your available growth options: resourcing (budget, team capacity), regulatory/legal limitations, brand positioning requirements, timing pressures, and audience accessibility challenges. These constraints aren't blockers—they're strategic filters that clarify what's actually viable for your specific situation.

The core financial guardrail is calculating your Target CAC using a systematic four-step process: determine ARPU (annual revenue per user), adjust for gross margin, map revenue timing over 12 months, choose a realistic payback period (3-12 months), and convert this into a maximum customer acquisition cost. For example, with $1,000 ARPU, 80% margin, and 6-month payback, your Target CAC becomes $400. Finally, you set a growth budget using target-based, runway-constrained, or revenue-percentage approaches. These guardrails create a systematic foundation that prevents the random tactic-chasing that kills most startups, ensuring every growth decision aligns with your business model and cash flow reality rather than hope-based experimentation.