The "Best Of..." Album
When it works...: The greatest hits album was...well, a hit. People loved it and they wanted more, literally they're writing in requests for songs they thought you greviously omitted from the original collection. That's bound to happen with a career spanning several decades, with hits charting in numerous holdings on the Billboard charts. There's just too many damn songs everyone loves from some of the biggest artists, that you pretty much HAVE to put out another albums worth of tunes. Yes, even a couple bad albums in order to keep up with the current musical trends (while keeping yourself relevant with the kids) cannot stop the "Best Of..." album from happening. "Best Of..." albums, if done right, can be showcase a more diverse (if not, completely successful) array of hits, and even in some cases will include live versions of the songs you love that were already on the last compilation.
Example: Frank Sinatra, Nothing But The Best
While it is VERY true that there is no shortage of Sinatra albums out there, the man has so much material that there is no such thing as the "definitive" single disc. With a career that spanned about fifty years, give or take a few, and so many hits that it makes the end of The Godfather look like Wall-E, you can infinitely repackage them into different compilations and yet not have too many complaints. A typical 20 song playlist holds a vast amount of combinations to display the work of his career, and you have enough choices that you can even put out a couple theme albums. (He has two love song compilations out there, which is more than most artists. Usually they stop at one and call it a night.) There's plenty of greatest hits and best of compilations for The Chairman, and there'll be plenty more because the mathematics are on his side.
When it gets ugly...: Ok, so not everyone that's hit the ten year plus mark in music deserves a "best of" Cd. In fact when your career revolves, for the most part, on a handful of hits, you really shouldn't be shitting on the goodwill of your fans by putting out ANOTHER compilation disc that includes the majority of the songs from the last compilation disc. If you haven't put in at least 20 years, or ten albums, worth of material out there, then frankly you should have been more careful with the greatest hits album. Fuck you, go home.
Example: The Eagles, The Best of the Eagles
Anyone who loves the Eagles has "Their Greatest Hits 1971-1985". Hell, that's one of the cassettes/CD's I can remember merely by the cover art, because my father LOVES the Eagles and he doesn't have this album. Why? Because if you look at the track listings, there's a massive overlap between the two, and on top of that there's songs on this album that should have fucking been on the first compilation in the first place. Who, tell me WHO, puts out an Eagles greatest hits compilation and fucking forgets Hotel California?! This just makes you feel stupid for buying the Greatest Hits album, and thus forces you to buy ANOTHER CD. Plus, this is an IMPORT CD, so you need to pay extra fucking money because France obviously LOVES the Eagles more than America.
Next Stop: The "Very Best Of..." album