It is narrated that the Prophet ﷺ once said:

"The first action for which a servant of Allah will be held accountable on the Day of Resurrection will be his prayers. If they are in order, he will have prospered and succeeded. If they are lacking, he will have failed and lost. If there is something defective in his obligatory prayers, then the Almighty Lord will say: See if My servant has any voluntary prayers that can complete what is insufficient in his obligatory prayers. The rest of his deeds will be judged the same way."