Saul chose three thousand men from Israel; two thousand were with him at Micmash and in the hill country of Bethel, and a thousand were with Jonathan at Gibeah in Benjamin. The rest of the men he sent back to their homes. 1 Sam 13:2
At one point Saul had rallied 330,000 men for the fight at Jabesh, why reduce that now?
I've seen this happen in churches. At some point there was a huge volunteer force and then some one thought it better to have quality over quantity. In my opinion you have to be very careful when making choices about who and how people can serve the Lord. I'm not saying you shouldn't have standards for certain positions, but I've seen and even drifted toward legalism and arrogance myself. It is easy to drift toward the ways of the world in judging someone's perceived effectiveness and skills. It seems to me that God often chooses the least of these to bring Him the most glory.
3 Jonathan attacked the Philistine outpost at Geba, and the Philistines heard about it. Then Saul had the trumpet blown throughout the land and said, "Let the Hebrews hear!" 4 So all Israel heard the news: "Saul has attacked the Philistine outpost, 1 Sam 13:3-4
Wow, how quickly we as leaders want to take the credit for someone else's accomplishments! We want to be front and center, to be famous, to make our name renown, instead of remaining humble and making sure that it is about making Jesus famous. We seem to be so interested in being the church on the cover, instead of the church on the corner.
…and now Israel has become a stench to the Philistines." 1 Sam 13:4
When it becomes about us, it is offensive to God and the rest of the world thinks we stink!