A person may receive only a fraction of his prayer

[AI] Ammar prayed two rakahs, and Abd al-Rahman ibn al-Harith said to him, "O Abu al-Yaqzan, I only see that you have made them brief." He said, "Have I reduced anything of their required parts?" He said, "No, but you made them brief." He said, "I hastened through them because of forgetfulness; I heard the Messenger of Allah ﷺ say: "A man may pray, yet perhaps he will have from his prayer only a tenth of it, a ninth of it, or an eighth of it, or a seventh of it"." He continued until he reached the end of the count.

أَنَّ عَمَّارًا صَلَّى رَكْعَتَيْنِ، فَقَالَ لَهُ عَبْدُ الرَّحْمَنِ بْنُ الْحَارِثِ: يَا أَبَا الْيَقْظَانِ، لَا أَرَاكَ إِلَّا قَدْ خَفَّفْتَهُمَا. قَالَ: هَلْ نَقَصْتُ مِنْ حُدُودِهَا شَيْئًا؟ قَالَ: لَا، وَلَكِنْ خَفَّفْتَهُمَا. قَالَ: إِنِّي بَادَرْتُ بِهِمَا السَّهْوَ، إِنِّي سَمِعْتُ رَسُولَ اللهِ ﷺ يَقُولُ: «إِنَّ الرَّجُلَ لَيُصَلِّي، وَلَعَلَّهُ أَنْ لَا يَكُونَ لَهُ مِنْ صَلَاتِهِ إِلَّا عُشْرُهَا، وَتُسْعُهَا، أَوْ ثُمُنُهَا، أَوْ سُبُعُهَا». حَتَّى انْتَهَى إِلَى آخِرِ الْعَدَدِ.

[AI] I heard the Messenger of Allah ﷺ saying, "A man may pray a prayer, and he may only have a tenth of it, or a ninth of it, or an eighth of it, or a seventh of it, or a sixth of it, until he reaches a certain number."

سَمِعْتُ رَسُولَ اللَّهِ ﷺ يَقُولُ «إِنَّ الرَّجُلَ لِيُصَلِّي الصَّلَاةَ وَلَعَلَّهُ لَا يَكُونُ لَهُ مِنْهَا إِلَّا عُشْرُهَا أَوْ تُسْعُهَا أَوْ ثُمُنُهَا أَوْ سُبُعُهَا أَوْ سُدْسُهَا» حَتَّى أَتَى عَلَى الْعَدَدِ

[AI] I heard the Messenger of Allah ﷺ say, "Indeed, a person may pray, and perhaps he will not have from his prayer except one-tenth of it, or one-ninth of it, or one-eighth of it, or one-seventh of it, until he reaches the last count."

سَمِعْتُ رَسُولَ اللهِ ﷺ يَقُولُ «إِنَّ الرَّجُلَ لَيُصَلِّي وَلَعَلَّهُ أَنْ لَا يَكُونَ لَهُ مِنْ صَلَاتِهِ إِلَّا عُشْرُهَا أَوْ تُسْعُهَا أَوْ ثُمْنُهَا أَوْ سُبْعُهَا حَتَّى انْتَهَى إِلَى آخِرِ الْعَدَدِ»