Why do some songs have a long period of nothing after the song is over?

kinda random.

but does anyone know why at the end of some songs, there is a long period of time that is just blank, no sound.

examples:

What Have We Been Waiting For? by Daphne Loves Derby and Your Guardian Angel by The Red Jumpsuit Apparatus

Why do some songs have a long period of nothing after the song is over?
Part of the reason might be because the music is fading out very slowly, but the recording technology doesn't pick up the faint sounds. Try turning the music up when the music fades out. Or maybe, like when a film is submitted to a contest, there has to be 30 seconds of nothing before and after the film and the remaining blank part is the 30 seconds of silence that was not edited out.