Why does Neptune rain diamonds?

Neptune is believed to rain diamonds due to the extreme pressure and temperatures within its atmosphere. As deep as 8,000 kilometers below the surface, conditions are so intense that carbon atoms can bond in a way that forms diamond structures. When these carbon compounds are subjected to the high pressures, they may crystallize into diamonds and potentially fall towards the planet's core. This phenomenon is similar to theories about other gas giants, like Uranus, which also have similar conditions.