Better A Poor But Wise Youth, Than An Old But Foolish King Who No Longer Knows How to Heed A Warning
When God is fed up with old religious systems and leaders who can no longer hear from Him, HE simply closes shop and moves on.
What Samuel was to Eli (a replacement) is what David was to Saul. Both leaders were old and deaf to what moved the heart of God and neither leader realized that God was done with them. He had found (for Himself) a young man in each instance, after HIS own heart. They would each serve HIM faithfully for 40 long years.
As Jesus wisely admonished:
Be careful how you hear.
Be careful what you hear.
Be careful who you are listening to.