I've had my ZZ plant (Zamioculcas zamiifolia) for about eight months now and I'm still amazed at how little it seems to care about neglect

I've had my ZZ plant (Zamioculcas zamiifolia) for about eight months now and I'm still amazed at how little it seems to care about neglect. I water it maybe once every three weeks and it just thrives in the corner of my living room with indirect light. My only question—is it normal for the leaflets to yellow slightly even when the soil isn't waterlogged? I'm wondering if it's just a natural part of the growth cycle or if I'm missing something.