I"m just picturing the one scene From My Hero Academia when Deku is in the test to enter the school and destroys the robot worth zero points at the end there.
Answering the question from below.
It has to do with time. How could he be sure that he'd be able to clear the S- rank dungeon in Japan and come back in time for the dual dungeon in Korea? Plus, he has his family's traumas consider.
I can't figure out why he didn't clear the s rank dungeon first if he was wanting to be as strong as possible, surely an s rank dungeon would give way more than any number of a ranks he could do in a day
LotusPetals