As Yoze walked up the stairs to arrive at the fourth floor, he noticed that, unlike the previous floor, there weren't any guards or people anywhere on the floor. Meaning that there wasn't any extra security blocking this room from being accessed so Yoze felt he should be able to go through this floor quickly.
When he arrived at the two giant doors that were his final obstacle to entering the fourth floor, Yoze didn't slow down and push the two doors open. By the time he was able to open a gap big enough to get through, Yoze felt disappointed at his discovery.
The floor was empty with not a single trace of any books, shelves, or even podiums. There was just nothing. The fourth floor was just an empty floor.
"Since I'm here there is no point in going back outside. I'll just cultivate until my talent marks refresh."