Or to put it another way, it's just noise, and sounds like a child pressing random keys on a keyboard
Some stuff may sound like that, especially to someone expecting something more conventional but if you listen to a spectrum of his music you'll actually see that he's exceptionally talented. It isn't all the aural assault that people tend to associate with his work.
Listen to some of the prepared piano on Druqks or some of the pad-filled ambient tunes from Selected Ambient Works 2 or even some of the more conventional ambient stuff from Selected Ambient Works 1, to get an idea of his less rhythmic stuff.
Lastly, there isn't a human alive, machine or piece of software in existence that can program a more complex rhythm pattern that actually manages to maintain a regular beat underneath the breaks, rolls, trills and rushes than Richard James ;-)