This may be like saying that the sun rising every morning is amazing (although we usually don't notice it), but Miles Davis's Kind of Blue is a masterpiece.
Well, duh! That's like saying, "Hey, you ought to hear the Fifth Symphony by that guy Beethoven. It's pretty good." Anyone who gets into classical music discovers Beethoven's Fifth, listens to it over and over, marvels at the construction and imagination, and then takes it for granted or ignores it. You know it's great, but after a certain point you don't listen to it regularly. I remember a music history professor during my undergraduate years who heard the Fifth Symphony performed after not hearing for a couple of years. She came into class gushing over it, amazed at how fresh it seemed.
That was my reaction the other night when I put on Kind of Blue. I had a very long day, including an elementary band concert, and when I got home I announced to Karen that I needed to go for one of the biggies - Miles or Ellington - to center myself. For some reason, I went with "the greatest jazz album of all time." Yeah, I knew it was good, but I had forgotten how good. Almost every detail is perfect - every chord voicing, every bass note (well, almost), every drumset choice. And every one of Miles' solos is the epitome of improvisation as beautiful melody - it's hard to imagine that any of the trumpet solos could be any better. Some of the saxophone aren't quite to that level, but they're pretty good. You can almost see the light bulb going off over Coltrane's head - he took the lessons of this album and ran with them. And although I sometimes find Jimmy Cobb's drumming boring, it seems just right on Kind of Blue.
Perfection is rare or nonexistent in this world, but Kind of Blue comes pretty close.