Arab Idol : First Step To Ego

the sixth episode of Arab Idol began with a lot of excitement, where Ragheb Alama surprised us about his dissatisfaction of the five participants that they started to get arrogant as he said that this might keep them away from the basic steps for a new star.
Ragheb assured that arrogance hurts the artist especially in the beginning of their way. He adviced them just to concentrate on practicing to give the best they have.
and here we ask our important question :
how does such participants with no enough competence get infected with arrogance that made them sure they are Idol ?