Why was no Book left by the Prophet?

The Prophet Muhammad did not present to his Companions the revelation collected and arranged in a single written volume. There are a number of good reasons for this:

• Because the revelation did not come down in one piece, but at intervals and was received continuously until the end of the Prophet's life.
• Because some verses were abrogated in the course of revelation, and therefore flexibility needed to be maintained.
• The ayat and suras were not always revealed in their final order, but were arranged later.
• The Prophet lived only nine days after the last revelation and was severely ill.
• There was no dispute or friction about the Qur'an during the time of the Prophet, as developed afterwards when he, as the final authority, was no longer available.