What causes the formation of Okazaki fragments?

The formation of Okazaki fragments is primarily caused by the discontinuous nature of DNA replication on the lagging strand during DNA synthesis. As DNA polymerase synthesizes DNA in the 5' to 3' direction, it encounters difficulties in replicating the lagging strand due to its opposite orientation. This results in the need for discontinuous synthesis, where short segments of DNA are synthesized in the direction opposite to the overall replication fork movement.