“I always encourage startups to really think very honestly about what your lifetime value of a customer is in terms of gross profit contribution and also be very thoughtful on your payback period.”

LTV Must Mean Gross Profit, Not GMV — And Payback Period Is What Actually Matters

Phil sees founders routinely present LTV figures that include gross merchandise value while taking a 1-10% take rate — creating numbers that look like $300 LTV when the true gross profit LTV is $3-30. Separately, a long LTV with a 24-month payback period creates a working capital crisis: you're writing a $1 check to Facebook today and waiting two years to get it back. The actionable rule: model LTV as gross profit dollars, model payback in months, and don't raise marketing spend until the math clears.