Duolingo prioritizes engagement over effectiveness because you cannot teach someone who has quit. Unlike schools that can keep students there even if they're bored, losing a learner for an app oftentimes means they will never be back.
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How does Duolingo balance the tradeoff between user engagement and learning effectiveness when designing the language learning app?
They always prioritize engagement. Why? Because it doesn't matter how effective you are. You can't teach somebody who's not there. When a user quits, they likely won't come back anymore.
Engagement and learning outcomes are not always at odds. But when they are, Duolingo prefers going for engagement. Intense lessons can have better outcomes but oftentimes lead to stress and frustration. Therefore, Duolingo tries to smooth frustration by converting short, intense lessons into longer, more enjoyable sessions.
Instead of teaching a complex grammar rule in a stressful five minutes, they stretch it over two hours with animations, playful interactions, and constant rewards to keep learners motivated with dopamine hits.
They opt for engagement because Duolingo is in an app rather than a school setting.
Unlike schools that hold students hostage there, even if it's boring, apps can easily lose users to other entertainment options. Even the tiniest frustration can drive users away to fall back on their easy TikTok scrolling, potentially forever. Therefore, they still teach you the material, but it will take longer and slower.