To me, music, especially dance music, is like, well, juggling balls. You start juggling with one ball, and then gradually build up by introducing more and more balls like the layering of instruments and voices, while keeping track of where each ball is and making sure none drops. Then when the song is ending, balls are removed one by one during juggling, till you're back with the original one.

Wraparound songs (or what I call songs where the beginning and end blend seamlessly together) will be like juggling the maximum number of balls at any one time: you play sleigh-of-hand by adding a ball with your left hand, while simultaneously losing a ball with your right.

Mixing 2 songs will be like juggling only blue balls, and doing a delayed introduction of red balls alternately into the juggling act where each blue ball is followed by a red. After this, the blue balls are slowly dropped out from the cycle till only the red balls remain and the new song emerges totally.

I know this sounds odd, but when I listen to music, my heart juggles balls.