poptimists | What makes a good best-of?

You don't have to read the review of the Radiohead best-of which got me thinking about this - the relevant bit is this: "This compilation is dominated by a pair of central ideas of what Radiohead sound like: emotionally nourishing, impressionistic balladeers, or crunchy, tech- and texture-savvy rockers. The outliers, moments when the band has dabbled more in mood, atmosphere, or a love of pure sound...aren't represented at all."

Now admittedly Scott's talking about the 2CD version not the 1CD version, which would have more room to roam, but my reaction was still "DUDE IT'S A BEST OF" - one of the things best ofs are for is to boil down an act to its essence, and with the best will in the world the experimental stuff has always been fringier to Radiohead than some might have you think.

But maybe you think best ofs are for representing a band's entire output, or spotlighting hidden depths, or presenting fan favourites, or or or - what do you look for in a compilation?