Then Saul said to his armorbearer, “Draw your sword, and thrust me through with it, lest these uncircumcised men come and thrust me through and abuse me.”
But his armorbearer would not, for he was greatly afraid. Therefore Saul took a sword and fell on it. 1 Samuel 31:4

What a tragic end to Israel’s first king.
In the beginning, he was a humble man that did not seek the kingdom, calling his tribe the least of all the tribes.
After some review, I’m not sure the start of his reign was the best. At his coronation Samuel said these words to the people, “But you have today rejected your God, who Himself saved you from all your adversities and your tribulations; and you have said to Him, ‘No, set a king over us!’” 1 Samuel 10:19
Basically, he is saying, “You’re choosing this man to reign over you instead of God!”
That’s not a responsibility I’d want, nor a responsibility anyone could live up to!

Saul then disobeyed God’s command concerning the Amalekites and offered a sacrifice, effectively proclaiming himself king and priest.
This is when God rejects his reign and gives it to David.
Now at the end, we find Saul taking his own life.

Everyone that rejects the Lord God takes their own life.
Jesus came to give life and give it more abundantly. To deny Him the opportunity to do this for you is suicide.