The rationality of a mobile robber:
“Steppe tribesmen traditionally would remain loyal to a leader for as long as he proved to be victorious in battle. There were no salaries. Temur understood this acutely. His military career was one long campaign, punctuated with only the briefest of interludes he needed to keep his armies on the move.”
Marozzi: (Life of) Tamerlane 1336-1405, in: Roberts (2011), pp. 202