Given the conditions under which learning often takes place, that is no surprise. Since so much of classroom experience is geared towards pandering to the lowest common denominator, and because so little of education takes individual difference into account, it is no wonder that students tune out. When education is individualized and effective, you cannot tear students away from their studies. Learning is intrinsically motivating to humans. Learning reinforces exploration and experimentation.
Learners wants to study.
Their hunger for knowledge is impatient and insatiable. It does not want to wait for a designer's idea of when the next topic should be covered. Learning is not a linear, ordered progression. It is more like a spiral. At first, we become familiar with the surface of a topic, then we learn about related topics, and we return to learn more about the first topic.