Second of Julia Barham's four scaling mistakes: teams get obsessed with growth immediately after launch instead of confirming product-market fit first. PMF often takes roughly two years and sometimes up to five — she cites Miro and Figma as examples of multi-year PMF timelines.
Pushing growth spend before PMF and ICP validation inverts the unit economics into a "leaky bucket": acquisition outpaces retention, so growth dollars leak out faster than they compound. Fix: validate retention and ideal-customer-profile fit before investing in growth.
Related: Product Market Fit Pyramid, PMF as Complaining Instead of Churning (Casey Winters), Marketplace PMF Takes ~2x Longer Than B2B SaaS PMF, "Don't Scale Chaos" (Leader-as-Bottleneck Mistake) (sibling mistake).
Before turning on growth spend, Barham's checklist is retention/churn signals plus a clearly defined Ideal Customer Profile — see Best-Fit Customer / ICP Reverse-Engineering for how to derive that ICP. Growth spend without both in place is what fills the leaky bucket faster rather than fixing the leak: it recruits more of the wrong customers, or the right customers into a product that hasn't earned their retention yet. She pairs this checklist with a PMF Sniff Test before deciding a product is actually ready for growth investment rather than more iteration.