When readers track streaks or earn badges, they get a clear sense of progress...

https://web-wiki.win/index.php/How_to_Write_UX_Copy_for_Rewards_Without_Sounding_Like_a_Used_Car_Salesman

When readers track streaks or earn badges, they get a clear sense of progress that encourages them to return. Personalization helps filter out the noise so people see stories that truly matter to them