1 Samuel 15:11 “I greatly regret that I have set up Saul as king, for he has turned back from following Me, and has not performed My commandments.” And it grieved Samuel, and he cried out to the Lord all night.
When Saul turned his back on God, it was Samuel who got to hear the bad news from God, news that was to grieve him to the extent that he had a bad night’s sleep.
There are many things which prevent us having a good sleep and knowing that someone you care about is in trouble is just one of those things.
What Samuel showed was great compassion as he lifted up this bad situation straight to God and continued all night.