Eno didn't approach the instrument from a pianistic orientation, but rather as a modernist painter. To him, synthesizers were electronic palettes; they could fabricate colors beyond the imaginations of their users. Eno maintained (still does) that he was not a musician. Hardly an insignificant claim, it defined an aesthetic absolutely crucial to the work he would accomplish after leaving Roxy Music: Vitality lies, not in professionalism, in the twin persona of composer and virtuoso, but in amateurism. The amateur is, above all, "a lover" (from the Latin, amator -- "lover, devotee, enthusiastic pursuer of an objective").
Eno left Roxy Music because he'd lost enthusiasm. Or as he put it, "[I]f you want to make a lot of money in rock music you have one good idea and then you do it again and again" (quoted in Eric Tamm's Brian Eno: His Music and the Vertical Color of Sound). Eno has had lots of ideas. As much as anyone in popular music, he has sought to explore - to make manifest -- possibilities latent in recording studios.