What are the reasons for the conquering successes of the Ottoman Turks?

What are the reasons for the conquering successes of the Ottoman Turks? What helped them strengthen their hold on power over the conquered countries?

The first reason was the weak opponents and the numerical superiority of the Ottoman army over them in the XIV-XV centuries. This applies to conquests in both Europe and Asia. The opposing states of the Ottomans often clashed with each other, for example, Byzantium with its western neighbors, and from 1351 the Turks began to expand into Europe. A big plus was the presence of artillery, that is how they took Constantinople in 1453. They strengthened their power by spreading Islam, for example, in the Balkans, Albania and Bosnia. They gave the conquered peoples the opportunity to do in the Ottoman army (Janissaries).