أَتُهْمِلُ وَاجِبَكَ وَقَدْ عَلِمْتَ عَاقِبَتَهُ؟
Do you neglect your duty despite knowing its consequences?
If the speaker genuinely seeks the answer, this is a real question. If the neglect is already known and the speaker rebukes it, the interrogative functions as reproach or disapproval.
Not every question is rhetorical. The intended force depends on prior knowledge, tone and contextual cues.