वर्षादि दक्षिणायनम् ॥ कZ_०२.२०.६२ ॥
varṣa-ādi dakṣiṇāyanam
দক্ষিণায়ণ বর্ষা (বর্ষাকাল) থেকে শুরু হয়।
Because rains constrain movement, affect agriculture and revenue timing, and require distinct administrative scheduling (storage, relief, road maintenance).