Is it likely that someone who is original and intelligent does not do very well at school? Should such a learner be called a failure? If not, why not?

Exams are not intelligence testing. The outcome of the exam only shows how much a student understands about the facts and numbers, equations and other data in textbooks or course books. Some learners are better than others to remember these facts and numbers and formulas. They get better marks even though in real-life situations they don't know the implementation of these formulas. Everyone has strengths and weaknesses of their own. Some learners understand and even go beyond ideas. Some learners are great at one thing but hopelessly bad at another. Everyone has their own individual skills that may or may not be noticeable in the scholarly report. The contractor from Hafeez was not great at studying. He ahs the building talent, though, and is now one of the leading architects. Thay is why students should be encouraged to exhibit and work on their skills. They are not supposed to be called failures.