“If we were to tomorrow wake up and say all right we're gonna charge for all of our great features very likely in two years another great app will do it for free.”

Protect the Free Core: Charging for Everything Invites a Free Competitor in 2 Years

Duolingo's strategic moat is its free tier. Locking the best features behind a paywall is a direct invitation for a well-funded rival to undercut on price. With AI lowering build costs, the window before a competitor arrives has shrunk dramatically. Protecting the free experience is not charity; it is competitive defense.