although they usually only make them for the hit songs, so I guess they wouldn't be able to predict that.

Heh, you think todays artists don't know their hits from their filler before the album is released?

Most hits you hear on the radio are manufactured, I'm afraid. Carefully and methodically. By your own example: The music videos are always made in advance, to coincide with the album's release, and the hits will get the high-budget treatment for the video. It's a giant marketing machine, and the videos are the TV commercials for the album.

There are lots of exceptions, of course. There are plenty of artists who make committed albums rather than manufactured hit/filler packages. But even those artists know which songs will "make it" and which ones won't. All artists know what their "A" material is.

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Tony Fabris