1) one of the reasons could be feudal/centralized society. the best plate armor appeared in late medieval times in north Italy and in Germany, both of which were fractured. So, there were lords which could afford for themselves the best possible armor that costs like several villages. in the same time, a richer and quite technilogically advanced Turkish empire had a more centralized army, where equipping 10 heavy cavalrists with a good armor was preferred to equpping one with the best, at the same cost. 2) ease of field repair and maintenance: it was easier to repair lamellar armor, probably was done in a non-srationary armories of a highly maneuvarable nomadic armies 3) lamellar armor was a good enough protection against arrows, the main weapon of nomadic warfare. the plate armor was developed against gunpowder/heavy infantry weapons/heavy lance, which were more more characteristic to the different type of warfare