It was narrated that ‘Ali ؓ said. Witr is not a must, but it is a Sunnah from the Messenger of Allah ﷺ and Allah, may He be glorified and exalted, is One and loves that which is odd numbered.
إِنَّ الْوَتْرَ لَيْسَ بِحَتْمٍ وَلَكِنَّهُ سُنَّةٌ مِنْ رَسُولِ اللهِ ﷺ وَإِنَّ اللهَ ﷻ وِتْرٌ يُحِبُّ الْوَتْرَ