Rabbi Yitzchak Zev Soloveitchik of Brisk (on the Torah, Parashat Va'era, section 48) proposes that the Ten Plagues did not come upon the Egyptians in order for them to release the Israelites, but rather to fulfill what was said to Avraham (Genesis 15:14): "But I will bring judgment on the nation that they serve." This is what is written (Exodus 7:1), "And the Lord said to Moses, 'See, I have made you like a god to Pharaoh.'" Rashi explains: "To chastise him with plagues and afflictions," which means to judge them for their evil deeds. Evidence for this is found in the Mishnah in Eduyot (chapter 2, mishnah 10), which states that the judgment of the Egyptians lasted twelve months, indicating that the plagues were a form of judgment and justice, not for the purpose of sending away the Israelites. Furthermore, Pharaoh's free will was taken away, so the plagues could not have been for the purpose of releasing the Israelites. Additionally, one could say that their purpose was to inform the inhabitants of the world that the sinner will die in his wickedness.

It has already been explained, and will be discussed further, that the plagues also came to instill faith in Hashem.