In the end it is so simple why this is labeled as the greatest jazz album on the list, melodies. Davis creates fantastic melodies that generate songs full of hooks as he and Coltrane play around with the ideas. One thing that is amazing is that this album was a one shot, unrehearsed recording of the songs as Davis laid them out for the guys before the recording started. It's hard for me to believe that anyone is that talented let alone six guys together, but here it is. Though the album is free thought, the songs aren't long and as I said before the melodies are infectious, pure genius. It may sound corny but if you only want to own one jazz album, this is the album to get.
By the way if you want to own two jazz albums get one that is not this list Dave Brubeck's Time Out. As hard as it is to believe it came out the same year as Kind of Blue and Giant Steps another album on the top 500 countdown.