Sometimes we will suspect that a student is struggling in our class as a result of a learning disability, but we don't feel like we have the extra time and energy to accommodate this student.
Maybe we are scared to approach the student with something like this and hope instead that our regular teaching strategies will be enough.
Or, we will try to help a student and find that he or she simply has no interest in being "accommodated."
Finally, and perhaps the most frustrating experience for both teacher and student, a student might have come to grips with his or her LD and has the enthusiasm and dedication needed to learn and apply new strategies, but somehow nothing we do seems to work to make this student a better writer.