Ringo Starr was the best rock / pop drummer of the sixties.

How to quantify good music: a guide.

Step one: Learn to play music. Either an instrument or as part of a highly-regarded choir, because "I can kinda sing on pitch" does not mean much.

Step two: Learn to actually pay attention to the music you listen to. I listen to any given song almost a dozen times before I feel I am qualified to pass judgement on it. I listen to it through as normal, then I listen to each instrument in it, then I listen to how everything meshes to form a coherent whole, then I listen to it again.

Step three: Make careful, studied observations about songs/albums/musicians/bands.

That's fairly accurate. It's pretty much the same way one quantifies any art, be it film, literature, or television. It all has a degree of subjectivity, but critics have fun saying these things and arguing about them endlessly anyways.

For my part, I looked at technical skill, innovation, creativity, musicality, influence, how the drummers played with their bands, overall popularity, and how well their work holds up today.

With that total package, I think Ringo is the hands down the best.

Why does popularity play any role into it?

Because it's hard to be influential if no one knows who you are. I guess I should have just rolled that into influence.