Ottoman Empire
The stagnation and decline, Stephen Lee argues, was relentless after the death of Suleiman in 1566, interrupted by a few short revivals or reform and recovery. The decline gathered speed so that the Empire in 1699 was, "a mere shadow of that which intimidated East and West alike in 1566." Although there are dissenting scholars, most historians point to "degenerate Sultans, incompetent Grand Viziers, debilitated and ill-equipped armies, corrupt officials, avaricious speculators, grasping enemies, and treacherous friends." The main cause was a failure of leadership, as Lee argues the first 10 sultans from 1292 to 1566, with one exception, had performed admirably. The next 13 sultans from 1566 to 1703, with two exceptions, were lackadaisical or incompetent rulers, says Lee. In a highly centralized system, the failure at the center proved fatal. A direct result was the strengthening of provincial elites who increasingly ignored Constantinople. Secondly the military strength of European enemies grew stronger and stronger, while the Ottoman armies and arms scarcely improved. Finally the Ottoman economic system grew distorted and impoverished, as war caused inflation, world trade moved in other directions, and the deterioration of law and order made economic progress difficult.

Q: Who argues that there was steep decline and stagnation after the death of Suleiman?
Stephen Lee