It's all genetics. Isn't nature pretty neat?

Other plants that exhibit this distichous arrangement that come to mind are some Haworthias (truncata), Gasterias, Aloe hardyi (when young), Aloe plicatilis, Ravenala madagascarensis, Phenakospermum guyanense, Wallichia disticha and Strelitzia nicolai. Some plants even exhibit tristichous leaf arrangements, which means leaves are arranged in 3 planes. A lot of palms are actually arranged in this manner - dypsis pembana, dypsis decaryi, dypsis madagascarensis, dypsis andapae. Then you also have plants that exhibit a spectacular spiral arrangement like aloe polyphylla and syagrus coronata.