a lucky shot?

But a certain man drew his bow at random and struck the king of Israel between the scale armor and the breastplate. Therefore he said to the driver of his chariot, "Turn around and carry me out of the battle, for I am wounded."
1 Kings 22:34

The demise of the wicked king Ahab was prophesied by God. At least twice God let him know that he would end his reign in misery. Ahab took every precaution in the Syrian war to save his life. But he wound up being deluded into going into battle. In a rare alliance with Judah, Ahab convinced king Jehoshaphat of Judah to ride into battle dressed in royal attire. Meanwhile, Ahab "disguised" himself in some fashion. Ahab's ruse was meant to draw the attack to Jehoshaphat. But God had other plans.

Ahab was still a high-profile target. He fought from a chariot with a driver. That made him at least an officer level target for the enemy to concentrate fire upon. Even then, the text makes it clear that God was using this battle in His own way to end Ahab's rule in Israel. No Syrian could officially take credit. The seemingly random, "lucky" shot of an unnamed archer was all God needed. The arrow struck in the one open space in Ahab's armor, wounding the king in a vital area and opening up a bleeding wound. The king bled to death in his chariot as he fled from battle. He could not hide from his fate.

The final note of prophetic irony comes when they clean the king's blood from the chariot at the pool of Samaria. There the dogs lick up the blood of Ahab the wicked king just as Elijah had prophesied (1 Kings 21:19). The rule of an evil king comes to a wicked end in the way that God had spoken that it would. It was the word of the Lord working to speak again to His people... even stray arrows will follow His command.