A “lucky charm” is only a cereal. There is nothing, really, that one can carry to ward off failure or ensure success. Absent God, success is about preparation, hard work, connection to power, and being in the right place at the right time with the right idea. With God however, it’s not that those things don’t matter, it is that they don’t have to matter.
The people of Israel thought that by taking God’s “Ark of the Covenant” they would be guaranteed success. After all, God surely wouldn’t let anything happen to his Ark. He’d have to guarantee success.
But God doesn’t work that way. After all the evil prevalent in Israel, God would not be forced to give success to them because of the Ark. The Ark was the seat of God’s presence, and if they were going to treat Him that way, He simply wouldn’t be present.
Eli understood that, and so did Ichabod’s mother.
God will never be in your debt. He will never owe you anything. He grants blessing according to His will and by His grace and those blessings can be removed as easily as they were given. His slowness in doing so shows that He is not capricious, but his patience, eventually, comes to an end.