In Spotify there are some playlists withautomatic crossfade. That means there's a smooth transition between songs. However, not everyone likes that, since the next song starts later (from minute 0:45, 0:26, 1:02...). That's why I thought it would be a good idea a to have the ability to switch it on and off depending on what the user prefers.
That way, there wouldn't be any problems with that.