It's a metaphorical phrase used to describe a situation where something good or beautiful is wasted on something that doesn't deserve it or doesn't match it.
Examples
- Spanish: Mira esa casa tan hermosa con ese carro viejo en la entrada. Tan linda jaula y tan feo el pichón.
- English: Look at that beautiful house with that old car in the driveway. Such a beautiful cage and such an ugly pigeon.