What were the reasons for Russia’s participation in the Russian-Turkish war?

The reasons for Russia’s participation in the wars with Turkey in the 18th-19th centuries were as follows:

The desire to secure their borders from the raids of the Crimean Tatars (completed by 1774, Crimea was annexed in 1783).
To get access to the Azov and Black seas, build a fleet there and start trading, completed by 1774.
Aid to the Balkan peoples, which were conquered by the Ottoman Turks, in 1812, thanks to this, for example, Serbia received autonomy, and in 1878 – full independence.
Striving to establish control over the straits between the Black and Aegean Seas and over the entire Black Sea.