Many students new to college do not know what it takes to be successful in the college environment. They understand good and bad grades in a general way, and they sense that they should attend classes, but that is where their knowledge begins and ends.
Most instructors know what a good student is - and is not. For one thing, a good student is not necessarily the most intelligent individual in the class.
By learning their characteristics, you may better understand the day-to-day and class-to-class behavior of students.