Gamification needs three things at once — a tight core loop, a metagame to strive at, and a profile that accumulates the user's investment.

Then you need a metag game, which for Duolingo is kind of like the path, but it's also the leaderboard, achievements, kind of long-term things that you're going to strive to such that you have like long-term, I guess, motivation uh to continue doing the thing. And then the profile is also critical because you build up a profile over time. It's a reflection of your investment inside the product experience. And so when you nail those three things, you can end up with a long-term learning journey that can be quite successful.