وَأَرْبَعًا قَبْلَ الْعَصْرِ، وَإِنْ شَاءَ رَكْعَتَيْنِ،
Translation: And four rakahs before Asr, or, if one wishes, two.
Four rakahs before Asr are recommended voluntary prayers, but not at the same level of emphasis as the two Sunnah rakahs of Fajr or the four before Zuhr.
The wording explicitly permits the choice of two rakahs, so performing two is not the abandonment of a fixed four-rakah obligation.
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Voluntary Prayers: Regular Sunnahs, Nawafil and Juristic Differences
وَأَرْبَعًا قَبْلَ الْعَصْرِ، وَإِنْ شَاءَ رَكْعَتَيْنِ،
Translation: And four rakahs before Asr, or, if one wishes, two.
Four rakahs before Asr are recommended voluntary prayers, but not at the same level of emphasis as the two Sunnah rakahs of Fajr or the four before Zuhr.
The wording explicitly permits the choice of two rakahs, so performing two is not the abandonment of a fixed four-rakah obligation.