Once upon a time the Shadows, riding their dark spider ships, descended upon planet Minbar in fire and fury. The spider fleet burned and blasted with lasers and missiles. Their attack toppled Minbari civilization.
The Shadows orbited the striken world. They watched, they waited.
Down on Minbar, chaos and conflict raged. In those dark days, only the strong, the smart and the lucky survived. Their descendants inherited these traits. They were brighter, swifter, tougher and fitter than ever. The species had evolved.
The Shadows were pleased, for that was what they wanted. The Uplift operation was successful! They left orbit and went home to Zha’ha’dum. They planned to return in three thousand years, to repeat the good deed.
But during those three thousand years, the Minbari evolved so fast that they lifted into space, and then into hyperspace. The Minbari tracked the Shadows back to Zha’ha’dum; and they did unto Zha’ha’dum what the Shadows had done unto Minbar.
In the resulting chaos and conflict, the Shadows evolved intelligence so high, and wisdom so deep, that they never played Uplift ever again.
Moral: No good deed goes unpunished.