The art of reading is defined when a reader read something which was initially incomprehensible to him, or, the text contained information that he didn’t possess early on. As he read the text and synthesized new knowledge, the art of reading successfully took place effectively elevating one’s knowledge to a certain specific degree.
If he read something that he initially knew or understood, he made nothing out of is reading activity.
Hence, challenge yourself with something new, everyday.
The statement above kinda related to this verse from Quran.