Going though the motions. Over and over in these old testament stories it’s about how quickly religion becomes a talisman, a superstition.
The Israelites obviously feel unguided in their role as chosen people, but god wants their hearts to be their guide, to improvise life on the theme of loving God.
Saul is preparing for battle here and Samuel, who must be really old by now, is late to do a sacrifice before. So Saul does it.
It’s a false move, the sacrifice is not the point the point is obedience and trust. The chapter includes Samuel’s rebuke of Saul and ends in a cliffhanger with the enemy philistines starting the attack.
Obedience sometimes requires sitting on your hands. Trust requires admitting you aren’t able to fix a problem. Doing this consistently is hard for human nature.
But there’s no other way…