Ever since Rui had been promoted to grade-five as a Martial Apprentice, he did not want to take any missions below his grade. Grade five missions were missions that posed some non-insignificant threat to Martial Apprentices. Either because a hostile Martial Apprentice was likely involved, because of extremely harsh environments, or because of powerful fauna.
The reason he had avoided missions with grades that were too low was because they did not push him as a Martial Artist. Grades one-to-four were trivially easy ninety-nine percent of the time, and none of them could make him feel endangered or draw out his survival instinct.
They were simply inconducive to his growth.
Thus, he had simply walked past the four outermost racks and shelves of missions graded one-to-four, they were not worth his time.