The 10th-floor challenge was unique in its own way.
The climbers who participated in the challenge had three choices, Either they win, give up or lose their life.
It was the floor that marked the starting point of the 'actual Tower'.
It was said that only those who cleared the 10th floor could be called a real climber of the Tower.
Below the 10th floor, all the floors were just considered as a second tutorial for the experience of newcomers from the point-view of higher floor people.
Those who had some talent were the only ones capable of making it above the 10th floor.
It doesn't mean that all players that passed the 10th floor had talents!
most of the time, all the summoners be it a good one with strong summons or a mediocre person who had no talent for the summoning, they would make it through regardless.
It was due to the unique trait of the test which favored the summoner-type climbers.
1. Shadows of Vice 2. Healer's Awakening: Beyond the Game