Quests like impressing a particular person, completing a certain number of tasks within a specific time frame, and so on.
Initially, Leo was heavily against the system and anything to do with it, but curiosity later led him to attempt completing a quest a few days after he got the system.
Leo could remember that day clearly.
The content of the quest was very simple; it was a week-long task, and all he had to do was make sure he sang continuously for an hour straight every day for seven days. This quest had been triggered after a music professor advised him to practise harder in singing.
Leo could be said to be one of the top students in his class, so his teachers generally paid attention to him. Due to his accumulating worry about an alien system being bound to him, which caused him to be distracted and perform below average in class, a teacher couldn't help but reach out to him, and this caused a quest to be generated.