What makes you come back to a language-learning app every day? 🌱

I've been building a language-learning platform and recently worked on a major update to improve the learning experience.
One thing I've been thinking about is consistency.
A lot of language-learning products can help you learn a word or complete a lesson, but getting someone to come back every day is a different challenge.
I'm experimenting with things like:
🔥 Streaks
⭐ XP & achievements
🎯 Daily challenges
🏆 Leaderboards
🌱 A visual tree that grows as you learn
I'd love to hear from other makers and language learners:
What actually makes you return to a learning product every day?
Is it streaks, progress visualization, competition, social features, content quality, or something else?
I'm especially interested in hearing what has worked for you personally.
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