The evidence for this is that it is established that some of the Companions and Successors omitted the qunūt in Witr. It is also established that some of them omitted it throughout the year except during half of Ramadan, while others performed the qunūt in Witr throughout the year (1). Their disagreement suggests that they were not all aware of any established practice of the Messenger of Allah, peace and blessings be upon him, performing the qunūt in every Witr prayer. This indicates that he would sometimes omit the qunūt in Witr. And Allah knows best.
Among those who related this disagreement was al-Tirmidhī, who said: “The scholars differed regarding the qunūt in Witr. Abd Allāh ibn Masūd held that the qunūt should be performed in Witr throughout the year, and he preferred that it be performed before bowing. This is the view of some scholars, and it was also held by Sufyān al-Thawrī, Ibn al-Mubārak, Ishāq, and the scholars of Kūfa.
“It has been reported of Ali ibn Abī Tālib that he would perform the qunūt only during the latter half of Ramadan, and that he would perform it after bowing. Some scholars adopted this view, including al-Shāfiī and Ahmad” (2). End quote.
– (2-6-3) The Place of the Qunūt in Witr
The qunūt is performed in the final rakʿah, after the recitation and before bowing. This is what is predominantly established from the practice of the Prophet, Allah’s blessings and peace be upon him. On occasion, however, he would perform the qunūt in Witr after bowing. And Allah knows best.
The evidence for this is as follows:
a) Ubayy ibn Kaʿb reported: “The Messenger of Allah, peace and blessings be upon him, would perform Witr and make the qunūt before bowing.” Narrated by Ibn Mājah. (3)