Do you remember that Madonna song 'Hollywood'? Neither do we. Which is why it's surprising to see it on her recent greatest-hits collection, 'Celebration.' Of course, it's not the first time an artist has messed with the best. Now, best-of records can be wonderful. And they simplify life by keeping us from buying more than one Steve Miller record. Still, performers and labels often find ways to take the "great" out of greatest hits, which is why we count down the 10 worst greatest-hits album mistakes.

10. Omission of Key Songs

Unless you're the Beatles and can't possibly fit all your greatest hits on one record, your best-of better include all the best. On 'The Very Best of Daryl Hall & John Oates,' the duo's yearning single 'She's Gone' -- one of their top three songs -- is noticeably missing. Yet, the inferior 'Wait for Me' is there. Of course, 'She's Gone' was included on subsequent greatest-hits albums, which leads us to ...

9. Too Many Greatest-Hits Albums

If you thought John Mellencamp's 'The Best That I Could Do 1978-1988' would be followed by a similarly priced 'Best That I Could Do 1988-,' you probably felt like a sucker when he released 'Words and Music' instead. That more expensive collection contained everything from the first greatest-hits album, plus songs that would have filled a follow-up, setting up the question, "Why didn't they just release 'Words and Music' to begin with?"

8. The "Previously Unreleased" Single

Bands want to make you think you're getting a bonus by adding a new song to a greatest-hits record. But acts