question #2 Sahih Muslim 738b, Book 6, Hadith 153 : What is the significance of observing Witr prayer in the night prayer routine?

He observed thirteen rak’ahs (in the night prayer). He observed eight rak’ahs and would then observe Witr and then observe two rak’ahs sitting, and when he wanted to bow he stood up and then bowed down, and then observed two rak’ahs in between the Adhan and lqama of the dawn prayer.