Eventually the Janissaries fell prey to the love of dunya, and lost discipline. They were doing other jobs and not training properly (because the treasury was declining and they were not being paid properly). Several times the Sultans tried to reform the Janissaries but were murdered. They also kept using bronze cannons which were too heavy to move once set on the field, because the bronze-casting department would lose their jobs if the army switched to lighter iron cannons like the Europeans. Dunya!