Answer:
The Mongols were very migratory. Their migratory pattern was based on climatic patterns. They needed to go where the rains and waters were so they and their animals could feed.
Because they had to always move, practising production and distribution was impracticable. The solution was to trade. When they had to settle at a place, they'd do so near already established settlements so that they could exchange their goods with what they can't produce. Hence, the reasons for their production and distribution patterns.
Cheers!