The Messenger of Allah (peace and blessings of Allah be upon him) said:
"Recite the Quran as long as your hearts are inclined to it. When they differ from it, then get up [and remove yourselves] from [reciting] it." [Bukhari, Muslim]
Ibn Katheer has stated that in this hadith, the Messenger of Allah has instructed this Community to recite the Quran as long as their hearts are attune to the recitation, thinking and pondering over its meaning. They are not to be reciting it while they are preoccupied or bored with its reading. In those cases, they will not be achieving the goal of its reading. Hence, they should discontinue reading under conditions like that.
"Purification of the Soul: Concept, Process and Means" - Jamaal al-Din M. Zarabozo, p. 305