Direct instruction can lead to daydreaming, loss of focus, or "Charlie Brown adult sounds" (blah blah blah), which happens to everyone during extended periods of focus.
Now add in someone who is not interested in the topic at hand, or the individual with ADHD, Autism, Specific Learning Disability, or other classifications or diagnoses.
The student will improve their ability to shift attention between tasks with 80% accuracy, as measured by teacher observation and data collection, in 3 out of 4 opportunities.